text:
Periodic table
From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
This article is about the table used in chemistry and physics. For other uses, see Periodic table (disambiguation).
Part of a series on the
Periodic table
Periodic table forms[show]
18-column
large cells
32-column (large cells)
Alternative forms
Janet's left step
Beyond period 7
Aufbau
Fricke
Pyykkö
Periodic table history[show]
Dmitri Mendeleev
predictions
Discovery of elements
Naming & etymology
for places
for people
controversies
(in East Asia)
Systematic element names
Sets of elements
By periodic table structure[show]
Groups (1–18)
1 (alkali metals)
2 (alkaline earth metals)
3
4
5
6
7
8
9
10
11
12
13
14
15 (pnictogens)
16 (chalcogens)
17 (halogens)
18 (noble gases)
Periods (1–7 ...)
1
2
3
4
5
6
7
8+
Aufbau
Fricke
Pyykkö
Blocks (s, p, d, f, ...)
Atomic orbitals
Aufbau principle
By metallic classification[show]
Metals
alkali
alkaline earth
transition
post-transition
lanthanide
actinide (superactinide)
Metalloids
dividing metals & nonmetals
Nonmetals
reactive nonmetals
noble gases
By other characteristics[show]
Coinage metals
Platinum-group metals
Precious metals
Refractory metals
Heavy metals
Light metals
Native metals
Noble metals
Main-group elements
Rare-earth elements
Transuranium, transplutonium elements
Major, minor & trans- actinides
Elements
List of chemical elements[show]
by abundance (in human body)
by atomic properties
by isotope stability
by annual production
by symbol
Properties of elements[show]
Atomic weight
Crystal structure
Electron affinity
configuration
Electronegativity (Allen, Pauling)
Goldschmidt classification
Nutrition
Valence
Data pages for elements[show]
Abundance
Atomic radius
Boiling point
Critical point
Density
Elasticity
Electrical resistivity
Electron affinity / configuration
Electronegativity
Hardness
Heat capacity / of fusion / of vaporization
Ionization energy
Melting point
Oxidation state
Speed of sound
Thermal conductivity / expansion coefficient
Vapor pressure
Book
Category
Chemistry Portal
v
t
e
The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties, whose structure shows periodic trends. Generally, within one row (period) the elements are metals to the left, and non-metals to the right, with the elements having similar chemical behaviours placed in the same column. Table rows are commonly called periods and columns are called groups. Six groups have accepted names as well as assigned numbers: for example, group 17 elements are the halogens; and group 18 are the noble gases. Also displayed are four simple rectangular areas or blocks associated with the filling of different atomic orbitals.
The organization of the periodic table can be used to derive relationships between the various element properties, but also the predicted chemical properties and behaviours of undiscovered or newly synthesized elements. Russian chemist Dmitri Mendeleev was the first to publish a recognizable periodic table in 1869, developed mainly to illustrate periodic trends of the then-known elements. He also predicted some properties of unidentified elements that were expected to fill gaps within the table. Most of his forecasts proved to be correct. Mendeleev's idea has been slowly expanded and refined with the discovery or synthesis of further new elements and the development of new theoretical models to explain chemical behaviour. The modern periodic table now provides a useful framework for analyzing chemical reactions, and continues to be widely used in chemistry, nuclear physics and other sciences.
All the elements from atomic numbers 1 (hydrogen) through 118 (oganesson) have been either discovered or synthesized, completing the first seven rows of the periodic table.[1][2] The first 98 elements exist in nature, although some are found only in trace amounts and others were synthesized in laboratories before being found in nature.[n 1] Elements 99 to 118 have only been synthesized in laboratories or nuclear reactors.[3] The synthesis of elements having higher atomic numbers is currently being pursued: these elements would begin an eighth row, and theoretical work has been done to suggest possible candidates for this extension. Numerous synthetic radionuclides of naturally occurring elements have also been produced in laboratories.
Contents
1 Overview
2 Grouping methods
2.1 Groups
2.2 Periods
2.3 Blocks
2.4 Metals, metalloids and nonmetals
3 Periodic trends and patterns
3.1 Electron configuration
3.2 Atomic radii
3.3 Ionization energy
3.4 Electronegativity
3.5 Electron affinity
3.6 Metallic character
3.7 Linking or bridging groups
4 History
4.1 First systemization attempts
4.2 Mendeleev's table
4.3 Second version and further development
5 Different periodic tables
5.1 The long- or 32-column table
5.2 Tables with different structures
6 Open questions and controversies
6.1 Placement of hydrogen and helium
6.2 Group 3 and its elements in periods 6 and 7
6.2.1 Lanthanum and actinium
6.2.2 Lutetium and lawrencium
6.2.3 Lanthanides and actinides
6.3 Groups included in the transition metals
6.4 Elements with unknown chemical properties
6.5 Further periodic table extensions
6.6 Element with the highest possible atomic number
6.7 Optimal form
7 See also
8 Notes
9 References
9.1 Bibliography
10 Further reading
11 External links
Overview
For a more detailed periodic table, see Periodic table (large cells).
hide
v
t
e
Periodic table
Group
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Alkali metals Alkaline earth metals Pnictogens Chalcogens Halogens Noble gases
Period
1
Hydrogen1H7000100800000000000♠1.008 Helium2He7000400260000000000♠4.0026
2
Lithium3Li7000694000000000000♠6.94 Beryllium4Be7000901220000000000♠9.0122 Boron5B7001108100000000000♠10.81 Carbon6C7001120110000000000♠12.011 Nitrogen7N7001140070000000000♠14.007 Oxygen8O7001159990000000000♠15.999 Fluorine9F7001189980000000000♠18.998 Neon10Ne7001201800000000000♠20.180
3
Sodium11Na7001229899999999999♠22.990 Magnesium12Mg7001243050000000000♠24.305 Aluminium13Al7001269820000000000♠26.982 Silicon14Si7001280850000000000♠28.085 Phosphorus15P7001309740000000000♠30.974 Sulfur16S7001320600000000000♠32.06 Chlorine17Cl7001354500000000000♠35.45 Argon18Ar7001399480000000000♠39.948
4
Potassium19K7001390980000000000♠39.098 Calcium20Ca7001400780000000000♠40.078 Scandium21Sc7001449560000000000♠44.956 Titanium22Ti7001478670000000000♠47.867 Vanadium23V7001509420000000000♠50.942 Chromium24Cr7001519960000000000♠51.996 Manganese25Mn7001549380000000000♠54.938 Iron26Fe7001558450000000000♠55.845 Cobalt27Co7001589330000000000♠58.933 Nickel28Ni7001586930000000000♠58.693 Copper29Cu7001635460000000000♠63.546 Zinc30Zn7001653800000000000♠65.38 Gallium31Ga7001697230000000000♠69.723 Germanium32Ge7001726300000000000♠72.630 Arsenic33As7001749220000000000♠74.922 Selenium34Se7001789710000000000♠78.971 Bromine35Br7001799040000000000♠79.904 Krypton36Kr7001837980000000000♠83.798
5
Rubidium37Rb7001854680000000000♠85.468 Strontium38Sr7001876200000000000♠87.62 Yttrium39Y7001889060000000000♠88.906 Zirconium40Zr7001912240000000000♠91.224 Niobium41Nb7001929060000000000♠92.906 Molybdenum42Mo7001959500000000000♠95.95 Technetium43Tc[98] Ruthenium44Ru7002101070000000000♠101.07 Rhodium45Rh7002102910000000000♠102.91 Palladium46Pd7002106420000000000♠106.42 Silver47Ag7002107870000000000♠107.87 Cadmium48Cd7002112410000000000♠112.41 Indium49In7002114820000000000♠114.82 Tin50Sn7002118710000000000♠118.71 Antimony51Sb7002121760000000000♠121.76 Tellurium52Te7002127600000000000♠127.60 Iodine53I7002126900000000000♠126.90 Xenon54Xe7002131289999999999♠131.29
6
Caesium55Cs7002132910000000000♠132.91 Barium56Ba7002137330000000000♠137.33 Lanthanum57La7002138910000000000♠138.91 Hafnium72Hf7002178490000000000♠178.49 Tantalum73Ta7002180950000000000♠180.95 Tungsten74W7002183840000000000♠183.84 Rhenium75Re7002186210000000000♠186.21 Osmium76Os7002190230000000000♠190.23 Iridium77Ir7002192220000000000♠192.22 Platinum78Pt7002195080000000000♠195.08 Gold79Au7002196970000000000♠196.97 Mercury80Hg7002200590000000000♠200.59 Thallium81Tl7002204380000000000♠204.38 Lead82Pb7002207200000000000♠207.2 Bismuth83Bi7002208980000000000♠208.98 Polonium84Po[209] Astatine85At[210] Radon86Rn[222]
7
Francium87Fr[223] Radium88Ra[226] Actinium89Ac[227] Rutherfordium104Rf[267] Dubnium105Db[268] Seaborgium106Sg[269] Bohrium107Bh[270] Hassium108Hs[270] Meitnerium109Mt[278] Darmstadtium110Ds[281] Roentgenium111Rg[282] Copernicium112Cn[285] Nihonium113Nh[286] Flerovium114Fl[289] Moscovium115Mc[290] Livermorium116Lv[293] Tennessine117Ts[294] Oganesson118Og[294]
Cerium58Ce7002140120000000000♠140.12 Praseodymium59Pr7002140910000000000♠140.91 Neodymium60Nd7002144240000000000♠144.24 Promethium61Pm[145] Samarium62Sm7002150360000000000♠150.36 Europium63Eu7002151960000000000♠151.96 Gadolinium64Gd7002157250000000000♠157.25 Terbium65Tb7002158930000000000♠158.93 Dysprosium66Dy7002162500000000000♠162.50 Holmium67Ho7002164930000000000♠164.93 Erbium68Er7002167260000000000♠167.26 Thulium69Tm7002168930000000000♠168.93 Ytterbium70Yb7002173050000000000♠173.05 Lutetium71Lu7002174970000000000♠174.97
Thorium90Th7002232040000000000♠232.04 Protactinium91Pa7002231040000000000♠231.04 Uranium92U7002238030000000000♠238.03 Neptunium93Np[237] Plutonium94Pu[244] Americium95Am[243] Curium96Cm[247] Berkelium97Bk[247] Californium98Cf[251] Einsteinium99Es[252] Fermium100Fm[257] Mendelevium101Md[258] Nobelium102No[259] Lawrencium103Lr[266]
1 (red)=Gas 3 (black)=Solid 80 (green)=Liquid 109 (gray)=Unknown Color of the atomic number shows state of matter (at 0 °C and 1 atm)
Primordial From decay Synthetic Border shows natural occurrence of the element
Standard atomic weight (Ar)[4]
Ca: 7001400780000000000♠40.078 — Formal short value, rounded (no uncertainty)[5]
Po: [209] — mass number of the most stable isotope
Background color shows subcategory in the metal–metalloid–nonmetal trend:
Metal Metalloid Nonmetal Unknown
chemical
properties
Alkali metal Alkaline earth metal Lanthanide Actinide Transition metal Post-transition metal Reactive nonmetal Noble gas
Each chemical element has a unique atomic number (Z) representing the number of protons in its nucleus.[n 2] Most elements have differing numbers of neutrons among different atoms, with these variants being referred to as isotopes. For example, carbon has three naturally occurring isotopes: all of its atoms have six protons and most have six neutrons as well, but about one per cent have seven neutrons, and a very small fraction have eight neutrons. Isotopes are never separated in the periodic table; they are always grouped together under a single element. Elements with no stable isotopes have the atomic masses of their most stable isotopes, where such masses are shown, listed in parentheses.[6]
In the standard periodic table, the elements are listed in order of increasing atomic number Z (the number of protons in the nucleus of an atom). A new row (period) is started when a new electron shell has its first electron. Columns (groups) are determined by the electron configuration of the atom; elements with the same number of electrons in a particular subshell fall into the same columns (e.g. oxygen and selenium are in the same column because they both have four electrons in the outermost p-subshell). Elements with similar chemical properties generally fall into the same group in the periodic table, although in the f-block, and to some respect in the d-block, the elements in the same period tend to have similar properties, as well. Thus, it is relatively easy to predict the chemical properties of an element if one knows the properties of the elements around it.[7]
As of 2016[update], the periodic table has 118 confirmed elements, from element 1 (hydrogen) to 118 (oganesson). Elements 113, 115, 117 and 118, the most recent discoveries, were officially confirmed by the International Union of Pure and Applied Chemistry (IUPAC) in December 2015. Their proposed names, nihonium (Nh), moscovium (Mc), tennessine (Ts) and oganesson (Og) respectively, were announced by the IUPAC in June 2016 and made official in November 2016.[8][9][10][11]
The first 94 elements occur naturally; the remaining 24, americium to oganesson (95–118), occur only when synthesized in laboratories. Of the 94 naturally occurring elements, 83 are primordial and 11 occur only in decay chains of primordial elements.[3] No element heavier than einsteinium (element 99) has ever been observed in macroscopic quantities in its pure form, nor has astatine (element 85); francium (element 87) has been only photographed in the form of light emitted from microscopic quantities (300,000 atoms).[12]
Grouping methods
Groups
Main article: Group (periodic table)
A group or family is a vertical column in the periodic table. Groups usually have more significant periodic trends than periods and blocks, explained below. Modern quantum mechanical theories of atomic structure explain group trends by proposing that elements within the same group generally have the same electron configurations in their valence shell.[13] Consequently, elements in the same group tend to have a shared chemistry and exhibit a clear trend in properties with increasing atomic number.[14] In some parts of the periodic table, such as the d-block and the f-block, horizontal similarities can be as important as, or more pronounced than, vertical similarities.[15][16][17]
Under an international naming convention, the groups are numbered numerically from 1 to 18 from the leftmost column (the alkali metals) to the rightmost column (the noble gases).[18] Previously, they were known by roman numerals. In America, the roman numerals were followed by either an "A" if the group was in the s- or p-block, or a "B" if the group was in the d-block. The roman numerals used correspond to the last digit of today's naming convention (e.g. the group 4 elements were group IVB, and the group 14 elements were group IVA). In Europe, the lettering was similar, except that "A" was used if the group was before group 10, and "B" was used for groups including and after group 10. In addition, groups 8, 9 and 10 used to be treated as one triple-sized group, known collectively in both notations as group VIII. In 1988, the new IUPAC naming system was put into use, and the old group names were deprecated.[19]
Some of these groups have been given trivial (unsystematic) names, as seen in the table below, although some are rarely used. Groups 3–10 have no trivial names and are referred to simply by their group numbers or by the name of the first member of their group (such as "the scandium group" for group 3), since they display fewer similarities and/or vertical trends.[18]
Elements in the same group tend to show patterns in atomic radius, ionization energy, and electronegativity. From top to bottom in a group, the atomic radii of the elements increase. Since there are more filled energy levels, valence electrons are found farther from the nucleus. From the top, each successive element has a lower ionization energy because it is easier to remove an electron since the atoms are less tightly bound. Similarly, a group has a top-to-bottom decrease in electronegativity due to an increasing distance between valence electrons and the nucleus.[20] There are exceptions to these trends: for example, in group 11, electronegativity increases farther down the group.[21]
hide
v
t
e
Groups in the Periodic table
IUPAC group
1
2
3a
a
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Mendeleev (I–VIII) IA IIA IIIB IVB VB VIB VIIB VIIIB IB IIB IIIB IVB VB VIB VIIB b
CAS (US, A-B-A) IA IIA IIIB IVB VB VIB VIIB VIIIB IB IIB IIIA IVA VA VIA VIIA VIIIA
old IUPAC (Europe, A-B) IA IIA IIIA IVA VA VIA VIIA VIIIB IB IIB IIIB IVB VB VIB VIIB 0
Trivial name Alkali metals Alkaline earth metalsr Coinage metals Triels Tetrels Pnictogensr Chalcogensr Halogensr Noble gasesr
Name by elementr Lithium group Beryllium group Scandium group Titanium group Vanadium group Chromium group Manganese group Iron group Cobalt group Nickel group Copper group Zinc group Boron group Carbon group Nitrogen group Oxygen group Fluorine group Helium or Neon group
Period 1 h H h He
Period 2 Li Be B C N O F Ne
Period 3 Na Mg Al Si P S Cl Ar
Period 4 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Period 5 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
Period 6 Cs Ba La Ce–Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Period 7 Fr Ra Ac Th–Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
a Group 3 has scandium (Sc) and yttrium (Y). For the rest of the group, sources differ as either being (1) lutetium (Lu) and lawrencium (Lr), or (2) lanthanum (La) and actinium (Ac), or (3) the whole set of 15+15 lanthanides and actinides. IUPAC has initiated a project to standardize the definition as either (1) Sc, Y, Lu and Lr, or (2) Sc, Y, La and Ac.[22]
b Group 18, the noble gases, were not discovered at the time of Mendeleev's original table. Later (1902), Mendeleev accepted the evidence for their existence, and they could be placed in a new "group 0", consistently and without breaking the periodic table principle.
r Group name as recommended by IUPAC.
h Hydrogen (H), while placed in group 1, is not considered to be part of the alkali metals.
Periods
Main article: Period (periodic table)
A period is a horizontal row in the periodic table. Although groups generally have more significant periodic trends, there are regions where horizontal trends are more significant than vertical group trends, such as the f-block, where the lanthanides and actinides form two substantial horizontal series of elements.[23]
Elements in the same period show trends in atomic radius, ionization energy, electron affinity, and electronegativity. Moving left to right across a period, atomic radius usually decreases. This occurs because each successive element has an added proton and electron, which causes the electron to be drawn closer to the nucleus.[24] This decrease in atomic radius also causes the ionization energy to increase when moving from left to right across a period. The more tightly bound an element is, the more energy is required to remove an electron. Electronegativity increases in the same manner as ionization energy because of the pull exerted on the electrons by the nucleus.[20] Electron affinity also shows a slight trend across a period. Metals (left side of a period) generally have a lower electron affinity than nonmetals (right side of a period), with the exception of the noble gases.[25]
Blocks
Main article: Block (periodic table)
Left to right: s-, f-, d-, p-block in the periodic table
Specific regions of the periodic table can be referred to as blocks in recognition of the sequence in which the electron shells of the elements are filled. Each block is named according to the subshell in which the "last" electron notionally resides.[26][n 3] The s-block comprises the first two groups (alkali metals and alkaline earth metals) as well as hydrogen and helium. The p-block comprises the last six groups, which are groups 13 to 18 in IUPAC group numbering (3A to 8A in American group numbering) and contains, among other elements, all of the metalloids. The d-block comprises groups 3 to 12 (or 3B to 2B in American group numbering) and contains all of the transition metals. The f-block, often offset below the rest of the periodic table, has no group numbers and comprises lanthanides and actinides.[27]
Metals, metalloids and nonmetals
Metals, metalloids, nonmetals, and elements with unknown chemical properties in the periodic table. Sources disagree on the classification of some of these elements.
According to their shared physical and chemical properties, the elements can be classified into the major categories of metals, metalloids and nonmetals. Metals are generally shiny, highly conducting solids that form alloys with one another and salt-like ionic compounds with nonmetals (other than noble gases). A majority of nonmetals are coloured or colourless insulating gases; nonmetals that form compounds with other nonmetals, feature covalent bonding. In between metals and nonmetals are metalloids, which have intermediate or mixed properties.[28]
Metal and nonmetals can be further classified into subcategories that show a gradation from metallic to non-metallic properties, when going left to right in the rows. The metals may be subdivided into the highly reactive alkali metals, through the less reactive alkaline earth metals, lanthanides and actinides, via the archetypal transition metals, and ending in the physically and chemically weak post-transition metals. Nonmetals may be simply subdivided into the polyatomic nonmetals, being nearer to the metalloids and show some incipient metallic character; the essentially nonmetallic diatomic nonmetals, nonmetallic and the almost completely inert, monatomic noble gases. Specialized groupings such as refractory metals and noble metals, are examples of subsets of transition metals, also known[29] and occasionally denoted.[30]
Placing elements into categories and subcategories based just on shared properties is imperfect. There is a large disparity of properties within each category with notable overlaps at the boundaries, as is the case with most classification schemes.[31] Beryllium, for example, is classified as an alkaline earth metal although its amphoteric chemistry and tendency to mostly form covalent compounds are both attributes of a chemically weak or post-transition metal. Radon is classified as a nonmetallic noble gas yet has some cationic chemistry that is characteristic of metals. Other classification schemes are possible such as the division of the elements into mineralogical occurrence categories, or crystalline structures. Categorizing the elements in this fashion dates back to at least 1869 when Hinrichs[32] wrote that simple boundary lines could be placed on the periodic table to show elements having shared properties, such as metals, nonmetals, or gaseous elements.
Periodic trends and patterns
Main article: Periodic trends
Electron configuration
Main article: Electronic configuration
Approximate order in which shells and subshells are arranged by increasing energy according to the Madelung rule
The electron configuration or organisation of electrons orbiting neutral atoms shows a recurring pattern or periodicity. The electrons occupy a series of electron shells (numbered 1, 2, and so on). Each shell consists of one or more subshells (named s, p, d, f and g). As atomic number increases, electrons progressively fill these shells and subshells more or less according to the Madelung rule or energy ordering rule, as shown in the diagram. The electron configuration for neon, for example, is 1s2 2s2 2p6. With an atomic number of ten, neon has two electrons in the first shell, and eight electrons in the second shell; there are two electrons in the s subshell and six in the p subshell. In periodic table terms, the first time an electron occupies a new shell corresponds to the start of each new period, these positions being occupied by hydrogen and the alkali metals.[33][34]
Periodic table trends (arrows show an increase)
Since the properties of an element are mostly determined by its electron configuration, the properties of the elements likewise show recurring patterns or periodic behaviour, some examples of which are shown in the diagrams below for atomic radii, ionization energy and electron affinity. It is this periodicity of properties, manifestations of which were noticed well before the underlying theory was developed, that led to the establishment of the periodic law (the properties of the elements recur at varying intervals) and the formulation of the first periodic tables.[33][34]
Atomic radii
Main article: Atomic radius
Atomic number plotted against atomic radius[n 4]
Atomic radii vary in a predictable and explainable manner across the periodic table. For instance, the radii generally decrease along each period of the table, from the alkali metals to the noble gases; and increase down each group. The radius increases sharply between the noble gas at the end of each period and the alkali metal at the beginning of the next period. These trends of the atomic radii (and of various other chemical and physical properties of the elements) can be explained by the electron shell theory of the atom; they provided important evidence for the development and confirmation of quantum theory.[35]
The electrons in the 4f-subshell, which is progressively filled across the lanthanide series, are not particularly effective at shielding the increasing nuclear charge from the sub-shells further out. The elements immediately following the lanthanides have atomic radii that are smaller than would be expected and that are almost identical to the atomic radii of the elements immediately above them.[36] Hence hafnium has virtually the same atomic radius (and chemistry) as zirconium, and tantalum has an atomic radius similar to niobium, and so forth. This is known as the lanthanide contraction. The effect of the lanthanide contraction is noticeable up to platinum (element 78), after which it is masked by a relativistic effect known as the inert pair effect.[37] The d-block contraction, which is a similar effect between the d-block and p-block, is less pronounced than the lanthanide contraction but arises from a similar cause.[36]
Ionization energy
Ionization energy: each period begins at a minimum for the alkali metals, and ends at a maximum for the noble gases
Main article: Ionization energy
The first ionization energy is the energy it takes to remove one electron from an atom, the second ionization energy is the energy it takes to remove a second electron from the atom, and so on. For a given atom, successive ionization energies increase with the degree of ionization. For magnesium as an example, the first ionization energy is 738 kJ/mol and the second is 1450 kJ/mol. Electrons in the closer orbitals experience greater forces of electrostatic attraction; thus, their removal requires increasingly more energy. Ionization energy becomes greater up and to the right of the periodic table.[37]
Large jumps in the successive molar ionization energies occur when removing an electron from a noble gas (complete electron shell) configuration. For magnesium again, the first two molar ionization energies of magnesium given above correspond to removing the two 3s electrons, and the third ionization energy is a much larger 7730 kJ/mol, for the removal of a 2p electron from the very stable neon-like configuration of Mg2+. Similar jumps occur in the ionization energies of other third-row atoms.[37]
Electronegativity
Main article: Electronegativity
Graph showing increasing electronegativity with growing number of selected groups
Electronegativity is the tendency of an atom to attract a shared pair of electrons.[38] An atom's electronegativity is affected by both its atomic number and the distance between the valence electrons and the nucleus. The higher its electronegativity, the more an element attracts electrons. It was first proposed by Linus Pauling in 1932.[39] In general, electronegativity increases on passing from left to right along a period, and decreases on descending a group. Hence, fluorine is the most electronegative of the elements,[n 5] while caesium is the least, at least of those elements for which substantial data is available.[21]
There are some exceptions to this general rule. Gallium and germanium have higher electronegativities than aluminium and silicon respectively because of the d-block contraction. Elements of the fourth period immediately after the first row of the transition metals have unusually small atomic radii because the 3d-electrons are not effective at shielding the increased nuclear charge, and smaller atomic size correlates with higher electronegativity.[21] The anomalously high electronegativity of lead, particularly when compared to thallium and bismuth, appears to be an artifact of data selection and data availability. Methods of calculation other than the Pauling method show the normal periodic trends for these elements.[40]
Electron affinity
Main article: Electron affinity
Dependence of electron affinity on atomic number.[41] Values generally increase across each period, culminating with the halogens before decreasing precipitously with the noble gases. Examples of localized peaks seen in hydrogen, the alkali metals and the group 11 elements are caused by a tendency to complete the s-shell (with the 6s shell of gold being further stabilized by relativistic effects and the presence of a filled 4f sub shell). Examples of localized troughs seen in the alkaline earth metals, and nitrogen, phosphorus, manganese and rhenium are caused by filled s-shells, or half-filled p- or d-shells.[42]
The electron affinity of an atom is the amount of energy released when an electron is added to a neutral atom to form a negative ion. Although electron affinity varies greatly, some patterns emerge. Generally, nonmetals have more positive electron affinity values than metals. Chlorine most strongly attracts an extra electron. The electron affinities of the noble gases have not been measured conclusively, so they may or may not have slightly negative values.[43]
Electron affinity generally increases across a period. This is caused by the filling of the valence shell of the atom; a group 17 atom releases more energy than a group 1 atom on gaining an electron because it obtains a filled valence shell and is therefore more stable.[43]
A trend of decreasing electron affinity going down groups would be expected. The additional electron will be entering an orbital farther away from the nucleus. As such this electron would be less attracted to the nucleus and would release less energy when added. In going down a group, around one-third of elements are anomalous, with heavier elements having higher electron affinities than their next lighter congenors. Largely, this is due to the poor shielding by d and f electrons. A uniform decrease in electron affinity only applies to group 1 atoms.[44]
Metallic character
The lower the values of ionization energy, electronegativity and electron affinity, the more metallic character the element has. Conversely, nonmetallic character increases with higher values of these properties.[45] Given the periodic trends of these three properties, metallic character tends to decrease going across a period (or row) and, with some irregularities (mostly) due to poor screening of the nucleus by d and f electrons, and relativistic effects,[46] tends to increase going down a group (or column or family). Thus, the most metallic elements (such as caesium and francium) are found at the bottom left of traditional periodic tables and the most nonmetallic elements (oxygen, fluorine, chlorine) at the top right. The combination of horizontal and vertical trends in metallic character explains the stair-shaped dividing line between metals and nonmetals found on some periodic tables, and the practice of sometimes categorizing several elements adjacent to that line, or elements adjacent to those elements, as metalloids.[47][48]
Linking or bridging groups
Sc, Y, La, Ac, Lu, Lr, Cu, Ag, Au, Zn, Cd, Hg, He, Ne, Ar, Kr, Xe, Rn
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
32-column periodic table showing, from left to right, the location of group 3; lutetium and lawrencium; groups 11–12; and the noble gases
From left to right across the four blocks of the long- or 32-column form of the periodic table are a series of linking or bridging groups of elements, located approximately between each block.[49] These groups, like the metalloids, show properties in between, or that are a mixture of, groups to either side. Chemically, the group 3 elements, scandium, yttrium, lanthanum and actinium behave largely like the alkaline earth metals[50] or, more generally, s block metals[51][52] but have some of the physical properties of d block transition metals.[53] Lutetium and lawrencium, at the end of the end of the f block, may constitute another linking or bridging group. Lutetium behaves chemically as a lanthanide but shows a mix of lanthanide and transition metal physical properties.[54][55] Lawrencium, as an analogue of lutetium, would presumable display like characteristics.[n 6] The coinage metals in group 11 (copper, silver, and gold) are chemically capable of acting as either transition metals or main group metals.[58] The volatile group 12 metals, zinc, cadmium and mercury are sometimes regarded as linking the d block to the p block. Notionally they are d block elements but they have few transition metal properties and are more like their p block neighbors in group 13.[59][60] The relatively inert noble gases, in group 18, bridge the most reactive groups of elements in the periodic table—the halogens in group 17 and the alkali metals in group 1.[49]
History
Main article: History of the periodic table
First systemization attempts
The discovery of the elements mapped to significant periodic table development dates (pre-, per- and post-)
In 1789, Antoine Lavoisier published a list of 33 chemical elements, grouping them into gases, metals, nonmetals, and earths.[61] Chemists spent the following century searching for a more precise classification scheme. In 1829, Johann Wolfgang Döbereiner observed that many of the elements could be grouped into triads based on their chemical properties. Lithium, sodium, and potassium, for example, were grouped together in a triad as soft, reactive metals. Döbereiner also observed that, when arranged by atomic weight, the second member of each triad was roughly the average of the first and the third;[62] this became known as the Law of Triads.[63] German chemist Leopold Gmelin worked with this system, and by 1843 he had identified ten triads, three groups of four, and one group of five. Jean-Baptiste Dumas published work in 1857 describing relationships between various groups of metals. Although various chemists were able to identify relationships between small groups of elements, they had yet to build one scheme that encompassed them all.[62]
In 1857, German chemist August Kekulé observed that carbon often has four other atoms bonded to it. Methane, for example, has one carbon atom and four hydrogen atoms.[64] This concept eventually became known as valency; different elements bond with different numbers of atoms.[65]
In 1862, Alexandre-Emile Béguyer de Chancourtois, a French geologist, published an early form of periodic table, which he called the telluric helix or screw. He was the first person to notice the periodicity of the elements. With the elements arranged in a spiral on a cylinder by order of increasing atomic weight, de Chancourtois showed that elements with similar properties seemed to occur at regular intervals. His chart included some ions and compounds in addition to elements. His paper also used geological rather than chemical terms and did not include a diagram; as a result, it received little attention until the work of Dmitri Mendeleev.[66]
In 1864, Julius Lothar Meyer, a German chemist, published a table with 44 elements arranged by valency. The table showed that elements with similar properties often shared the same valency.[67] Concurrently, English chemist William Odling published an arrangement of 57 elements, ordered on the basis of their atomic weights. With some irregularities and gaps, he noticed what appeared to be a periodicity of atomic weights among the elements and that this accorded with "their usually received groupings".[68] Odling alluded to the idea of a periodic law but did not pursue it.[69] He subsequently proposed (in 1870) a valence-based classification of the elements.[70]
Newlands' periodic table, as presented to the Chemical Society in 1866, and based on the law of octaves
English chemist John Newlands produced a series of papers from 1863 to 1866 noting that when the elements were listed in order of increasing atomic weight, similar physical and chemical properties recurred at intervals of eight; he likened such periodicity to the octaves of music.[71][72] This so termed Law of Octaves was ridiculed by Newlands' contemporaries, and the Chemical Society refused to publish his work.[73] Newlands was nonetheless able to draft a table of the elements and used it to predict the existence of missing elements, such as germanium.[74] The Chemical Society only acknowledged the significance of his discoveries five years after they credited Mendeleev.[75]
In 1867, Gustavus Hinrichs, a Danish born academic chemist based in America, published a spiral periodic system based on atomic spectra and weights, and chemical similarities. His work was regarded as idiosyncratic, ostentatious and labyrinthine and this may have militated against its recognition and acceptance.[76][77]
Mendeleev's table
Dmitri Mendeleev, watercolour by Ilya Repin
Mendeleev's periodic table from his book An Attempt Towards a Chemical Conception of the Ether
A version of Mendeleev's 1869 periodic table: An experiment on a system of elements based on their atomic weights and chemical similarities. This early arrangement presents the periods vertically, and the groups horizontally.
Russian chemistry professor Dmitri Mendeleev and German chemist Julius Lothar Meyer independently published their periodic tables in 1869 and 1870, respectively.[78] Mendeleev's table was his first published version; that of Meyer was an expanded version of his (Meyer's) table of 1864.[79] They both constructed their tables by listing the elements in rows or columns in order of atomic weight and starting a new row or column when the characteristics of the elements began to repeat.[80]
The recognition and acceptance afforded to Mendeleev's table came from two decisions he made. The first was to leave gaps in the table when it seemed that the corresponding element had not yet been discovered.[81] Mendeleev was not the first chemist to do so, but he was the first to be recognized as using the trends in his periodic table to predict the properties of those missing elements, such as gallium and germanium.[82] The second decision was to occasionally ignore the order suggested by the atomic weights and switch adjacent elements, such as tellurium and iodine, to better classify them into chemical families.
Mendeleev published in 1869, using atomic weight to organize the elements, information determinable to fair precision in his time. Atomic weight worked well enough to allow Mendeleev to accurately predict the properties of missing elements.
Following the discovery, in 1911, by Ernest Rutherford of the atomic nucleus, it was proposed that the integer count of the nuclear charge is identical to the sequential place of each element in the periodic table. In 1913, Henry Moseley using X-ray spectroscopy confirmed this proposal experimentally. Moseley determined the value of the nuclear charge of each element, and showed that Mendeleev's ordering actually places the elements in sequential order by nuclear charge.[83] Nuclear charge is identical to proton count, and determines the value of the atomic number (Z) of each element. Using atomic number gives a definitive, integer-based sequence for the elements. Moseley predicted, in 1913, that the only elements still missing between aluminium (Z=13) and gold (Z=79) were Z = 43, 61, 72, and 75, all of which were later discovered. The atomic number is the absolute definition of an element, and gives a factual basis for the ordering of the periodic table. The periodic table is used to predict the properties of new synthetic elements before they are produced and studied.[84]
Second version and further development
Mendeleev's 1871 periodic table with eight groups of elements. Dashes represented elements unknown in 1871.
Eight-column form of periodic table, updated with all elements discovered to 2016
In 1871, Mendeleev published his periodic table in a new form, with groups of similar elements arranged in columns rather than in rows, and those columns numbered I to VIII corresponding with the element's oxidation state. He also gave detailed predictions for the properties of elements he had earlier noted were missing, but should exist.[85] These gaps were subsequently filled as chemists discovered additional naturally occurring elements.[86] It is often stated that the last naturally occurring element to be discovered was francium (referred to by Mendeleev as eka-caesium) in 1939.[87] Plutonium, produced synthetically in 1940, was identified in trace quantities as a naturally occurring element in 1971.[88]
The popular[89] periodic table layout, also known as the common or standard form (as shown at various other points in this article), is attributable to Horace Groves Deming. In 1923, Deming, an American chemist, published short (Mendeleev style) and medium (18-column) form periodic tables.[90][n 7] Merck and Company prepared a handout form of Deming's 18-column medium table, in 1928, which was widely circulated in American schools. By the 1930s Deming's table was appearing in handbooks and encyclopaedias of chemistry. It was also distributed for many years by the Sargent-Welch Scientific Company.[91][92][93]
With the development of modern quantum mechanical theories of electron configurations within atoms, it became apparent that each period (row) in the table corresponded to the filling of a quantum shell of electrons. Larger atoms have more electron sub-shells, so later tables have required progressively longer periods.[94]
Glenn T. Seaborg, in 1945, suggested a new periodic table showing the actinides as belonging to a second f-block series.
In 1945, Glenn Seaborg, an American scientist, made the suggestion that the actinide elements, like the lanthanides, were filling an f sub-level. Before this time the actinides were thought to be forming a fourth d-block row. Seaborg's colleagues advised him not to publish such a radical suggestion as it would most likely ruin his career. As Seaborg considered he did not then have a career to bring into disrepute, he published anyway. Seaborg's suggestion was found to be correct and he subsequently went on to win the 1951 Nobel Prize in chemistry for his work in synthesizing actinide elements.[95][96][n 8]
Although minute quantities of some transuranic elements occur naturally,[3] they were all first discovered in laboratories. Their production has expanded the periodic table significantly, the first of these being neptunium, synthesized in 1939.[97] Because many of the transuranic elements are highly unstable and decay quickly, they are challenging to detect and characterize when produced. There have been controversies concerning the acceptance of competing discovery claims for some elements, requiring independent review to determine which party has priority, and hence naming rights.[98] In 2010, a joint Russia–US collaboration at Dubna, Moscow Oblast, Russia, claimed to have synthesized six atoms of tennessine (element 117), making it the most recently claimed discovery. It, along with nihonium (element 113), moscovium (element 115), and oganesson (element 118), are the four most recently named elements, whose names all became official on 28 November 2016.[99]
Different periodic tables
The long- or 32-column table
The periodic table in 32-column format
The modern periodic table is sometimes expanded into its long or 32-column form by reinstating the footnoted f-block elements into their natural position between the s- and d-blocks. Unlike the 18-column form this arrangement results in "no interruptions in the sequence of increasing atomic numbers".[100] The relationship of the f-block to the other blocks of the periodic table also becomes easier to see.[101] Jensen advocates a form of table with 32 columns on the grounds that the lanthanides and actinides are otherwise relegated in the minds of students as dull, unimportant elements that can be quarantined and ignored.[102] Despite these advantages the 32-column form is generally avoided by editors on account of its undue rectangular ratio (compared to a book page ratio),[103] and the familiarity of chemists with the modern form (as introduced by Seaborg).[104]
Tables with different structures
Main article: Alternative periodic tables
Within 100 years of the appearance of Mendeleev's table in 1869 it has been estimated that around 700 different periodic table versions were published.[105] As well as numerous rectangular variations, other periodic table formats have been shaped, for example,[n 9] like a circle, cube, cylinder, building, spiral, lemniscate,[106] octagonal prism, pyramid, sphere, or triangle. Such alternatives are often developed to highlight or emphasize chemical or physical properties of the elements that are not as apparent in traditional periodic tables.[105]
Theodor Benfey's spiral periodic table
A popular[107] alternative structure is that of Theodor Benfey (1960). The elements are arranged in a continuous spiral, with hydrogen at the centre and the transition metals, lanthanides, and actinides occupying peninsulas.[108]
Most periodic tables are two-dimensional;[3] three-dimensional tables are known to as far back as at least 1862 (pre-dating Mendeleev's two-dimensional table of 1869). More recent examples include Courtines' Periodic Classification (1925),[109] Wringley's Lamina System (1949),[110] Giguère's Periodic helix (1965)[111] and Dufour's Periodic Tree (1996).[112] Going one further, Stowe's Physicist's Periodic Table (1989)[113] has been described as being four-dimensional (having three spatial dimensions and one colour dimension).[114]
The various forms of periodic tables can be thought of as lying on a chemistry–physics continuum.[115] Towards the chemistry end of the continuum can be found, as an example, Rayner-Canham's "unruly"[116] Inorganic Chemist's Periodic Table (2002),[117] which emphasizes trends and patterns, and unusual chemical relationships and properties. Near the physics end of the continuum is Janet's Left-Step Periodic Table (1928). This has a structure that shows a closer connection to the order of electron-shell filling and, by association, quantum mechanics.[118] A somewhat similar approach has been taken by Alper,[119] albeit criticized by Eric Scerri as disregarding the need to display chemical and physical periodicity.[120] Somewhere in the middle of the continuum is the ubiquitous common or standard form of periodic table. This is regarded as better expressing empirical trends in physical state, electrical and thermal conductivity, and oxidation numbers, and other properties easily inferred from traditional techniques of the chemical laboratory.[121] Its popularity is thought to be a result of this layout having a good balance of features in terms of ease of construction and size, and its depiction of atomic order and periodic trends.[69][122]
hide
v
t
e
Left-step periodic table (by Charles Janet)
f1 f2 f3 f4 f5 f6 f7 f8 f9 f10 f11 f12 f13 f14 d1 d2 d3 d4 d5 d6 d7 d8 d9 d10 p1 p2 p3 p4 p5 p6 s1 s2
1s H He
2s Li Be
2p 3s B C N O F Ne Na Mg
3p 4s Al Si P S Cl Ar K Ca
3d 4p 5s Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr
4d 5p 6s Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I  Xe Cs Ba
4f 5d 6p 7s La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra
5f 6d 7p 8s Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og 119 120
f-block d-block p-block s-block
This form of periodic table is more congruent with the order in which electron shells are ideally filled according to the Madelung rule, as shown in the accompanying sequence in the left margin (read from top to bottom, left to right). In reality, the filling of electron shells is characterized by a number of irregularities.
Open questions and controversies
Placement of hydrogen and helium
Simply following electron configurations, hydrogen (electronic configuration 1s1) and helium (1s2) should be placed in groups 1 and 2, above lithium (1s22s1) and beryllium (1s22s2).[26] While such a placement is common for hydrogen, it is rarely used for helium outside of the context of electron configurations: When the noble gases (then called "inert gases") were first discovered around 1900, they were known as "group 0", reflecting no chemical reactivity of these elements known at that point, and helium was placed on the top of that group, as it did share the extreme chemical inertness seen throughout the group. As the group changed its formal number, many authors continued to assign helium directly above neon, in group 18; one of the examples of such placing is the current IUPAC table.[123]
Hydrogen's chemical properties are not very close to those of the alkali metals, which occupy group 1. On this basis it is sometimes placed elsewhere. A common alternative is at the top of group 17[120] given hydrogen's strictly univalent and largely non-metallic chemistry, and the strictly univalent and non-metallic chemistry of fluorine (the element otherwise at the top of group 17). Sometimes, to show hydrogen has properties corresponding to both those of the alkali metals and the halogens, it is shown at the top of the two columns simultaneously.[124] Another suggestion is above carbon in group 14: placed that way, it fits well into the trends of increasing ionization potential values and electron affinity values, and is not too far from the electronegativity trend, even though hydrogen cannot show the tetravalence characteristic of the heavier group 14 elements.[125] Finally, hydrogen is sometimes placed separately from any group; this is based on its general properties being different from those of the elements in any other group. The other period 1 element, helium, is sometimes placed separately from any group as well.[126] The property that distinguishes helium from the rest of the noble gases (even though the extraordinary inertness of helium is extremely close to that of neon and argon)[127] is that in its closed electron shell, helium has only two electrons in the outermost electron orbital, while the rest of the noble gases have eight.
Group 3 and its elements in periods 6 and 7
Although scandium and yttrium are always the first two elements in group 3, the identity of the next two elements is not completely settled. They are commonly lanthanum and actinium, and less often lutetium and lawrencium. The two variants originate from historical difficulties in placing the lanthanides in the periodic table, and arguments as to where the f block elements start and end.[128][n 10][n 11] It has been claimed that such arguments are proof that, "it is a mistake to break the [periodic] system into sharply delimited blocks".[130] A third variant shows the two positions below yttrium as being occupied by the lanthanides and the actinides.
Chemical and physical arguments have been made in support of lutetium and lawrencium[131][132] but the majority of authors seem unconvinced.[133] Most working chemists are not aware there is any controversy.[134] In December 2015 an IUPAC project was established to make a recommendation on the matter.[135]
Lanthanum and actinium

La and Ac below Y
Lanthanum and actinium are commonly depicted as the remaining group 3 members.[136][n 12] It has been suggested that this layout originated in the 1940s, with the appearance of periodic tables relying on the electron configurations of the elements and the notion of the differentiating electron. The configurations of caesium, barium and lanthanum are [Xe]6s1, [Xe]6s2 and [Xe]5d16s2. Lanthanum thus has a 5d differentiating electron and this establishes it "in group 3 as the first member of the d-block for period 6".[137] A consistent set of electron configurations is then seen in group 3: scandium [Ar]3d14s2, yttrium [Kr]4d15s2 and lanthanum [Xe]5d16s2. Still in period 6, ytterbium was assigned an electron configuration of [Xe]4f135d16s2 and lutetium [Xe]4f145d16s2, "resulting in a 4f differentiating electron for lutetium and firmly establishing it as the last member of the f-block for period 6".[137] Later spectroscopic work found that the electron configuration of ytterbium was in fact [Xe]4f146s2. This meant that ytterbium and lutetium—the latter with [Xe]4f145d16s2—both had 14 f-electrons, "resulting in a d- rather than an f- differentiating electron" for lutetium and making it an "equally valid candidate" with [Xe]5d16s2 lanthanum, for the group 3 periodic table position below yttrium.[137] Lanthanum has the advantage of incumbency since the 5d1 electron appears for the first time in its structure whereas it appears for the third time in lutetium, having also made a brief second appearance in gadolinium.[138]
In terms of chemical behaviour,[139] and trends going down group 3 for properties such as melting point, electronegativity and ionic radius,[140][141] scandium, yttrium, lanthanum and actinium are similar to their group 1–2 counterparts. In this variant, the number of f electrons in the most common (trivalent) ions of the f-block elements consistently matches their position in the f-block.[142] For example, the f-electron counts for the trivalent ions of the first three f-block elements are Ce 1, Pr 2 and Nd 3.[143]
Lutetium and lawrencium

Lu and Lr below Y
In other tables, lutetium and lawrencium are the remaining group 3 members.[n 13] Early techniques for chemically separating scandium, yttrium and lutetium relied on the fact that these elements occurred together in the so-called "yttrium group" whereas La and Ac occurred together in the "cerium group".[137] Accordingly, lutetium rather than lanthanum was assigned to group 3 by some chemists in the 1920s and 30s.[n 14] Several physicists in the 1950s and '60s favoured lutetium, in light of a comparison of several of its physical properties with those of lanthanum.[137] This arrangement, in which lanthanum is the first member of the f-block, is disputed by some authors since lanthanum lacks any f-electrons. It has been argued that this is not valid concern given other periodic table anomalies—thorium, for example, has no f-electrons yet is part of the f-block.[144] As for lawrencium, its gas phase atomic electron configuration was confirmed in 2015 as [Rn]5f147s27p1. Such a configuration represents another periodic table anomaly, regardless of whether lawrencium is located in the f-block or the d-block, as the only potentially applicable p-block position has been reserved for nihonium with its predicted configuration of [Rn]5f146d107s27p1.[145][n 15]
Chemically, scandium, yttrium and lutetium (and presumably lawrencium) behave like trivalent versions of the group 1–2 metals.[147] On the other hand, trends going down the group for properties such as melting point, electronegativity and ionic radius, are similar to those found among their group 4–8 counterparts.[137] In this variant, the number of f electrons in the gaseous forms of the f-block atoms usually matches their position in the f-block. For example, the f-electron counts for the first five f-block elements are La 0, Ce 1, Pr 3, Nd 4 and Pm 5.[137]
Lanthanides and actinides

Markers below Y
A few authors position all thirty lanthanides and actinides in the two positions below yttrium (usually via footnote markers). This variant emphasizes similarities in the chemistry of the 15 lanthanide elements (La–Lu), possibly at the expense of ambiguity as to which elements occupy the two group 3 positions below yttrium, and a 15-column wide f block (there can only be 14 elements in any row of the f block).[n 16]
Groups included in the transition metals
The definition of a transition metal, as given by IUPAC, is an element whose atom has an incomplete d sub-shell, or which can give rise to cations with an incomplete d sub-shell.[148] By this definition all of the elements in groups 3–11 are transition metals. The IUPAC definition therefore excludes group 12, comprising zinc, cadmium and mercury, from the transition metals category.
Some chemists treat the categories "d-block elements" and "transition metals" interchangeably, thereby including groups 3–12 among the transition metals. In this instance the group 12 elements are treated as a special case of transition metal in which the d electrons are not ordinarily involved in chemical bonding. The 2007 report of mercury(IV) fluoride (HgF4), a compound in which mercury would use its d electrons for bonding, has prompted some commentators to suggest that mercury can be regarded as a transition metal.[149] Other commentators, such as Jensen,[150] have argued that the formation of a compound like HgF4 can occur only under highly abnormal conditions; indeed, its existence is currently disputed. As such, mercury could not be regarded as a transition metal by any reasonable interpretation of the ordinary meaning of the term.[150]
Still other chemists further exclude the group 3 elements from the definition of a transition metal. They do so on the basis that the group 3 elements do not form any ions having a partially occupied d shell and do not therefore exhibit any properties characteristic of transition metal chemistry.[151] In this case, only groups 4–11 are regarded as transition metals. Though the group 3 elements show few of the characteristic chemical properties of the transition metals, they do show some of their characteristic physical properties (on account of the presence in each atom of a single d electron).[53]
Elements with unknown chemical properties
Although all elements up to oganesson have been discovered, of the elements above hassium (element 108), only copernicium (element 112), nihonium (element 113), and flerovium (element 114) have known chemical properties, and only for copernicium is there enough evidence for a conclusive categorisation at present. The other elements may behave differently from what would be predicted by extrapolation, due to relativistic effects; for example, flerovium has been predicted to possibly exhibit some noble-gas-like properties, even though it is currently placed in the carbon group.[152] The current experimental evidence still leaves open the question of whether flerovium behaves more like a metal or a noble gas.[153]
Further periodic table extensions
Main article: Extended periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Ununennium Unbinilium Unbiunium
Unquadquadium Unquadpentium Unquadhexium Unquadseptium Unquadoctium Unquadennium Unpentnilium Unpentunium Unpentbium Unpenttrium Unpentquadium Unpentpentium Unpenthexium Unpentseptium Unpentoctium Unpentennium Unhexnilium Unhexunium Unhexbium Unhextrium Unhexquadium Unhexpentium Unhexhexium Unhexseptium Unhexoctium Unhexennium Unseptnilium Unseptunium Unseptbium
Unbibium Unbitrium Unbiquadium Unbipentium Unbihexium Unbiseptium Unbioctium Unbiennium Untrinilium Untriunium Untribium Untritrium Untriquadium Untripentium Untrihexium Untriseptium Untrioctium Untriennium Unquadnilium Unquadunium Unquadbium Unquadtrium
Periodic table with eight rows, extended to element 172[154]
It is unclear whether new elements will continue the pattern of the current periodic table as period 8, or require further adaptations or adjustments. Seaborg expected the eighth period to follow the previously established pattern exactly, so that it would include a two-element s-block for elements 119 and 120, a new g-block for the next 18 elements, and 30 additional elements continuing the current f-, d-, and p-blocks, culminating in element 168, the next noble gas.[155] More recently, physicists such as Pekka Pyykkö have theorized that these additional elements do not follow the Madelung rule, which predicts how electron shells are filled and thus affects the appearance of the present periodic table. There are currently several competing theoretical models for the placement of the elements of atomic number less than or equal to 172. In all of these it is element 172, rather than element 168, that emerges as the next noble gas after oganesson, although these must be regarded as speculative as no complete calculations have been done beyond element 122.[156]
Element with the highest possible atomic number
The number of possible elements is not known. A very early suggestion made by Elliot Adams in 1911, and based on the arrangement of elements in each horizontal periodic table row, was that elements of atomic weight greater than circa 256 (which would equate to between elements 99 and 100 in modern-day terms) did not exist.[157] A higher—more recent—estimate is that the periodic table may end soon after the island of stability,[158] which is expected to centre around element 126, as the extension of the periodic and nuclides tables is restricted by proton and neutron drip lines.[159] Other predictions of an end to the periodic table include at element 128 by John Emsley,[3] at element 137 by Richard Feynman,[160] and at element 155 by Albert Khazan.[3][n 17]
Bohr model
The Bohr model exhibits difficulty for atoms with atomic number greater than 137, as any element with an atomic number greater than 137 would require 1s electrons to be travelling faster than c, the speed of light.[161] Hence the non-relativistic Bohr model is inaccurate when applied to such an element.
Relativistic Dirac equation
The relativistic Dirac equation has problems for elements with more than 137 protons. For such elements, the wave function of the Dirac ground state is oscillatory rather than bound, and there is no gap between the positive and negative energy spectra, as in the Klein paradox.[162] More accurate calculations taking into account the effects of the finite size of the nucleus indicate that the binding energy first exceeds the limit for elements with more than 173 protons. For heavier elements, if the innermost orbital (1s) is not filled, the electric field of the nucleus will pull an electron out of the vacuum, resulting in the spontaneous emission of a positron.[163] This does not happen if the innermost orbital is filled, so that element 173 is not necessarily the end of the periodic table.[160]
Optimal form
The many different forms of periodic table have prompted the question of whether there is an optimal or definitive form of periodic table.[164] The answer to this question is thought to depend on whether the chemical periodicity seen to occur among the elements has an underlying truth, effectively hard-wired into the universe, or if any such periodicity is instead the product of subjective human interpretation, contingent upon the circumstances, beliefs and predilections of human observers. An objective basis for chemical periodicity would settle the questions about the location of hydrogen and helium, and the composition of group 3. Such an underlying truth, if it exists, is thought to have not yet been discovered. In its absence, the many different forms of periodic table can be regarded as variations on the theme of chemical periodicity, each of which explores and emphasizes different aspects, properties, perspectives and relationships of and among the elements.[n 18]
See also
Chemistry portal
Book: Periodic table
Abundance of the chemical elements
Atomic electron configuration table
Element collecting
List of chemical elements
List of periodic table-related articles
Names for sets of chemical elements
Standard model
Table of nuclides
Template:Spectral lines of the elements
The Mystery of Matter: Search for the Elements (PBS film)
Timeline of chemical element discoveries
Notes
Jump up ^ The elements discovered initially by synthesis and later in nature are technetium (Z=43), promethium (61), astatine (85), neptunium (93), plutonium (94), americium (95), curium (96), berkelium (97) and californium (98).
Jump up ^ An element zero (i.e. a substance composed purely of neutrons), is included in a few alternate presentations, for example, in the Chemical Galaxy.
Jump up ^ There is an inconsistency and some irregularities in this convention. Thus, helium is shown in the p-block but is actually an s-block element, and (for example) the d-subshell in the d-block is actually filled by the time group 11 is reached, rather than group 12.
Jump up ^ The noble gases, astatine, francium, and all elements heavier than americium were left out as there is no data for them.
Jump up ^ While fluorine is the most electronegative of the elements under the Pauling scale, neon is the most electronegative element under other scales, such as the Allen scale.
Jump up ^ While Lr is thought to have p rather than d electron in its ground-state electron configuration, and would therefore be expected to be volatile metal capable of forming a +1 cation in solution, no evidence of either of these properties has been able to be obtained despite experimental attempts to do so.[56] It was originally expected to have a d electron in its electron configuration[56] and this may still be the case for metallic lawrencium, whereas gas phase atomic lawrencium is very likely thought to have a p electron.[57]
Jump up ^ An antecedent of Deming's 18-column table may be seen in Adams' 16-column Periodic Table of 1911. Adams omits the rare earths and the "radioactive elements" (i.e. the actinides) from the main body of his table and instead shows them as being "careted in only to save space" (rare earths between Ba and eka-Yt; radioactive elements between eka-Te and eka-I). See: Elliot Q. A. (1911). "A modification of the periodic table". Journal of the American Chemical Society. 33(5): 684–688 (687).
Jump up ^ A second extra-long periodic table row, to accommodate known and undiscovered elements with an atomic weight greater than bismuth (thorium, protactinium and uranium, for example), had been postulated as far back as 1892. Most investigators considered that these elements were analogues of the third series transition elements, hafnium, tantalum and tungsten. The existence of a second inner transition series, in the form of the actinides, was not accepted until similarities with the electron structures of the lanthanides had been established. See: van Spronsen, J. W. (1969). The periodic system of chemical elements. Amsterdam: Elsevier. p. 315–316, ISBN 0-444-40776-6.
Jump up ^ See The Internet database of periodic tables for depictions of these kinds of variants.
Jump up ^ But for the existence of the lanthanides the composition of group 3 would not have been a source of any special interest, since scandium, yttrium, lanthanum and actinium exhibit the same gradual change in properties as do calcium, strontium, barium and radium in group 2.[129]
Jump up ^ The detachment of the lanthanides from the main body of the periodic table has been attributed to the Czech chemist Bohuslav Brauner who, in 1902, allocated all of them ("Ce etc.") to one position in group 4, below zirconium. This arrangement was referred to as the "asteroid hypothesis", in analogy to asteroids occupying a single orbit in the solar system. Before this time the lanthanides were generally (and unsuccessfully) placed throughout groups I to VIII of the older 8-column form of periodic table. Although predecessors of Brauner's 1902 arrangement are recorded from as early as 1895, he is known to have referred to the "chemistry of asteroids" in an 1881 letter to Mendeleev. Other authors assigned all of the lanthanides to either group 3, groups 3 and 4, or groups 2, 3 and 4. In 1922 Niels Bohr continued the detachment process by locating the lanthanides between the s- and d-blocks. In 1949 Glenn T. Seaborg (re)introduced the form of periodic table that is popular today, in which the lanthanides and actinides appear as footnotes. Seaborg first published his table in a classified report dated 1944. It was published again by him in 1945 in Chemical and Engineering News, and in the years up to 1949 several authors commented on, and generally agreed with, Seaborg's proposal. In that year he noted that the best method for presenting the actinides seemed to be by positioning them below, and as analogues of, the lanthanides. See: Thyssen P. and Binnemans K. (2011). "Accommodation of the Rare Earths in the Periodic Table: A Historical Analysis". In K. A. Gschneider Jr. (ed). Handbook on the Physics and Chemistry of the Rare Earths. 41. Amsterdam: Elsevier, pp. 1–94; Seaborg G. T. (1994). Origin of the Actinide Concept'. In K. A. Gschneider Jr. (ed). Handbook on the Physics and Chemistry of the Rare Earths. 18. Amsterdam: Elsevier, pp. 1–27.
Jump up ^ For examples of this table see Atkins et al. (2006). Shriver & Atkins Inorganic Chemistry (4th ed.). Oxford: Oxford University Press • Myers et al. (2004). Holt Chemistry. Orlando: Holt, Rinehart & Winston • Chang R. (2000). Essential Chemistry (2nd ed.). Boston: McGraw-Hill
Jump up ^ For examples of the group 3 = Sc-Y-Lu-Lr table see Rayner-Canham G. & Overton T. (2013). Descriptive Inorganic Chemistry (6th ed.). New York: W. H. Freeman and Company • Brown et al. (2009). Chemistry: The Central Science (11th ed.). Upper Saddle River, New Jersey: Pearson Education • Moore et al. (1978). Chemistry. Tokyo: McGraw-Hill Kogakusha
Jump up ^ The phenomenon of different separation groups is caused by increasing basicity with increasing radius, and does not constitute a fundamental reason to show Lu, rather than La, below Y. Thus, among the Group 2 alkaline earth metals, Mg (less basic) belongs in the "soluble group" and Ca, Sr and Ba (more basic) occur in the "ammonium carbonate group". Nevertheless, Mg, Ca, Sr and Ba are routinely collocated in Group 2 of the periodic table. See: Moeller et al. (1989). Chemistry with Inorganic Qualitative Analysis (3rd ed.). SanDiego: Harcourt Brace Jovanovich, pp. 955–956, 958.
Jump up ^ Even if metallic lawrencium has a p electron, simple modelling studies suggest it will behave like a lanthanide,[146] as do the rest of the late actinides.[143]
Jump up ^ For examples of the group 3 = Ln and An table see Housecroft C. E. & Sharpe A. G. (2008). Inorganic Chemistry (3rd ed.). Harlow: Pearson Education • Halliday et al. (2005). Fundamentals of Physics (7th ed.). Hoboken, NewJersey: John Wiley & Sons • Nebergall et. al. (1980). General Chemistry (6th ed.). Lexington: D. C. Heath and Company
Jump up ^ Karol (2002, p. 63) contends that gravitational effects would become significant when atomic numbers become astronomically large, thereby overcoming other super-massive nuclei instability phenomena, and that neutron stars (with atomic numbers on the order of 1021) can arguably be regarded as representing the heaviest known elements in the universe. See: Karol P. J. (2002). "The Mendeleev–Seaborg periodic table: Through Z = 1138 and beyond". Journal of Chemical Education 79 (1): 60–63.
Jump up ^ Scerri, one of the foremost authorities on the history of the periodic table,[165] favoured the concept of an optimal form of periodic table but has recently changed his mind and now supports the value of a plurality of periodic tables.[164]
References
Jump up ^ "Chemistry: Four elements added to periodic table". BBC News. 4 January 2016. Archived from the original on 4 January 2016.
Jump up ^ St. Fleur, Nicholas (1 December 2016). "Four New Names Officially Added to the Periodic Table of Elements". New York Times. Archived from the original on 14 August 2017.
^ Jump up to: a b c d e f Emsley, J. (2011). Nature's Building Blocks: An A-Z Guide to the Elements (New ed.). New York, NY: Oxford University Press. ISBN 978-0-19-960563-7.
Jump up ^ Meija, J.; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
Jump up ^ IUPAC 2016, Table 2, 3 combined; uncertainty removed.
Jump up ^ Greenwood & Earnshaw, pp. 24–27
Jump up ^ Gray, p. 6
Jump up ^ CNN, Ashley Strickland. "New elements on the periodic table are named". CNN. Archived from the original on 10 June 2016. Retrieved 11 June 2016.
Jump up ^ "Discovery and assignment of elements with atomic numbers 113, 115, 117 and 118". International Union of Pure and Applied Chemistry. 30 December 2015. Archived from the original on 13 June 2016.
Jump up ^ "Hello, Nihonium. Scientists Name 4 New Elements On The Periodic Table". NPR.org. Archived from the original on 10 June 2016. Retrieved 11 June 2016.
Jump up ^ Koppenol, W. H. (2002). "Naming of New Elements (IUPAC Recommendations 2002)" (PDF). Pure and Applied Chemistry. 74 (5): 787–791. doi:10.1351/pac200274050787. Archived (PDF) from the original on 31 October 2008.
Jump up ^ Silva, Robert J. (2006). "Fermium, Mendelevium, Nobelium and Lawrencium". In Morss, L. R.; Edelstein, N. M.; Fuger, J. The Chemistry of the Actinide and Transactinide Elements (3rd ed.). Dordrecht, The Netherlands: Springer Science+Business Media. ISBN 1-4020-3555-1.
Jump up ^ Scerri 2007, p. 24
Jump up ^ Messler, R. W. (2010). The essence of materials for engineers. Sudbury, MA: Jones & Bartlett Publishers. p. 32. ISBN 0-7637-7833-8.
Jump up ^ Bagnall, K. W. (1967). "Recent advances in actinide and lanthanide chemistry". In Fields, P. R.; Moeller, T. Advances in chemistry, Lanthanide/Actinide chemistry. Advances in Chemistry. 71. American Chemical Society. pp. 1–12. doi:10.1021/ba-1967-0071. ISBN 0-8412-0072-6.
Jump up ^ Day, M. C., Jr.; Selbin, J. (1969). Theoretical inorganic chemistry (2nd ed.). New York: Nostrand-Rienhold Book Corporation. p. 103. ISBN 0-7637-7833-8.
Jump up ^ Holman, J.; Hill, G. C. (2000). Chemistry in context (5th ed.). Walton-on-Thames: Nelson Thornes. p. 40. ISBN 0-17-448276-0.
^ Jump up to: a b Leigh, G. J. (1990). Nomenclature of Inorganic Chemistry: Recommendations 1990. Blackwell Science. ISBN 0-632-02494-1.
Jump up ^ Fluck, E. (1988). "New Notations in the Periodic Table" (PDF). Pure Appl. Chem. IUPAC. 60 (3): 431–436. doi:10.1351/pac198860030431. Archived (PDF) from the original on 25 March 2012. Retrieved 24 March 2012.
^ Jump up to: a b Moore, p. 111
^ Jump up to: a b c Greenwood & Earnshaw, p. 30
Jump up ^ "The constitution of group 3 of the periodic table". IUPAC. 2015-12-18.
Jump up ^ Stoker, S. H. (2007). General, organic, and biological chemistry. New York: Houghton Mifflin. p. 68. ISBN 978-0-618-73063-6. OCLC 52445586.
Jump up ^ Mascetta, J. (2003). Chemistry The Easy Way (4th ed.). New York: Hauppauge. p. 50. ISBN 978-0-7641-1978-1. OCLC 52047235.
Jump up ^ Kotz, J.; Treichel, P.; Townsend, John (2009). Chemistry and Chemical Reactivity, Volume 2 (7th ed.). Belmont: Thomson Brooks/Cole. p. 324. ISBN 978-0-495-38712-1. OCLC 220756597.
^ Jump up to: a b Gray, p. 12
Jump up ^ Jones, C. (2002). d- and f-block chemistry. New York: J. Wiley & Sons. p. 2. ISBN 978-0-471-22476-1. OCLC 300468713.
Jump up ^ Silberberg, M. S. (2006). Chemistry: The molecular nature of matter and change (4th ed.). New York: McGraw-Hill. p. 536. ISBN 0-07-111658-3.
Jump up ^ Manson, S. S.; Halford, G. R. (2006). Fatigue and durability of structural materials. Materials Park, Ohio: ASM International. p. 376. ISBN 0-87170-825-6.
Jump up ^ Bullinger, H-J. (2009). Technology guide: Principles, applications, trends. Berlin: Springer-Verlag. p. 8. ISBN 978-3-540-88545-0.
Jump up ^ Jones, B. W. (2010). Pluto: Sentinel of the outer solar system. Cambridge: Cambridge University Press. pp. 169–71. ISBN 978-0-521-19436-5.
Jump up ^ Hinrichs, G. D. (1869). "On the classification and the atomic weights of the so-called chemical elements, with particular reference to Stas's determinations". Proceedings of the American Association for the Advancement of Science. 18 (5): 112–124. Archived from the original on 2 August 2016.
^ Jump up to: a b Myers, R. (2003). The basics of chemistry. Westport, CT: Greenwood Publishing Group. pp. 61–67. ISBN 0-313-31664-3.
^ Jump up to: a b Chang, R. (2002). Chemistry (7 ed.). New York: McGraw-Hill. pp. 289–310; 340–42. ISBN 0-07-112072-6.
Jump up ^ Greenwood & Earnshaw, p. 27
^ Jump up to: a b Jolly, W. L. (1991). Modern Inorganic Chemistry (2nd ed.). McGraw-Hill. p. 22. ISBN 978-0-07-112651-9.
^ Jump up to: a b c Greenwood & Earnshaw, p. 28
Jump up ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "Electronegativity".
Jump up ^ Pauling, L. (1932). "The Nature of the Chemical Bond. IV. The Energy of Single Bonds and the Relative Electronegativity of Atoms". Journal of the American Chemical Society. 54 (9): 3570–3582. Bibcode:1932JAChS..54.2610C. doi:10.1021/ja01348a011.
Jump up ^ Allred, A. L. (1960). "Electronegativity values from thermochemical data". Journal of Inorganic and Nuclear Chemistry. Northwestern University. 17 (3–4): 215–221. doi:10.1016/0022-1902(61)80142-5. Retrieved 11 June 2012.
Jump up ^ Huheey, Keiter & Keiter, p. 42
Jump up ^ Siekierski, S.; Burgess, J. (2002). Concise chemistry of the elements. Chichester: Horwood Publishing. pp. 35‒36. ISBN 1-898563-71-3.
^ Jump up to: a b Chang, pp. 307–309
Jump up ^ Huheey, Keiter & Keiter, pp. 42, 880–81
Jump up ^ Yoder, C. H.; Suydam, F. H.; Snavely, F. A. (1975). Chemistry (2nd ed.). Harcourt Brace Jovanovich. p. 58. ISBN 0-15-506465-7.
Jump up ^ Huheey, Keiter & Keiter, pp. 880–85
Jump up ^ Sacks, O. (2009). Uncle Tungsten: Memories of a chemical boyhood. New York: Alfred A. Knopf. pp. 191, 194. ISBN 0-375-70404-3.
Jump up ^ Gray, p. 9
^ Jump up to: a b MacKay, K. M.; MacKay, R. A.; Henderson, W. (2002). Introduction to Modern Inorganic Chemistry (6th ed.). Cheltenham: Nelson Thornes. pp. 194–196. ISBN 0-7487-6420-8.
Jump up ^ Remy, H. (1956). Kleinberg, J., ed. Treatise on Inorganic Chemistry. 2. Amsterdam: Elsevier. p. 30.
Jump up ^ Phillips, C. S. G.; Williams, R. J. P. (1966). Inorganic Chemistry. Oxford: Clarendon Press. pp. 4–5.
Jump up ^ King, R. B. (1995). Inorganic chemistry of main group elements. New York: Wiley-VCH. p. 289.
^ Jump up to: a b Greenwood & Earnshaw, p. 947
Jump up ^ Spedding, F. H.; Beadry, B. J. (1968). "Lutetium". In Hampel, C. A. The Encyclopedia of the Chemical Elements. Reinhold Book Corporation. pp. 374–378.
Jump up ^ Settouti, N.; Aourag, H. (2014). "A Study of the Physical and Mechanical Properties of Lutetium Compared with Those of Transition Metals: A Data Mining Approach". JOM. 67 (1): 87–93. Bibcode:2015JOM....67a..87S. doi:10.1007/s11837-014-1247-x.
^ Jump up to: a b Silva, Robert J. (2011). "Chapter 13. Fermium, Mendelevium, Nobelium, and Lawrencium". In Morss, Lester R.; Edelstein, Norman M.; Fuger, Jean. The Chemistry of the Actinide and Transactinide Elements. Netherlands: Springer. doi:10.1007/978-94-007-0211-0_13. ISBN 978-94-007-0210-3.
Jump up ^ Sato, T. K.; Asai, M.; Borschevsky, A.; Stora, T.; Sato, N.; Kaneya, Y.; Tsukada, K.; Düllman, Ch. E.; Eberhardt, K.; Eliav, E.; Ichikawa, S.; Kaldor, U.; Kratz, J. V.; Miyashita, S.; Nagame, Y.; Ooe, K.; Osa, A.; Renisch, D.; Runke, J.; Schädel, M.; Thörle-Pospiech, P.; Toyoshima, A.; Trautmann, N. (9 April 2015). "Measurement of the first ionization potential of lawrencium, element 103" (PDF). Nature. 520 (7546): 209–11. Bibcode:2015Natur.520..209S. doi:10.1038/nature14342. PMID 25855457.
Jump up ^ Steele, D. The Chemistry of the Metallic Elements. Oxford: Pergamon Press. p. 67.
Jump up ^ Greenwood, N. N.; Earnshaw, A. Chemistry of the Elements (2nd ed.). Oxford: Elsevier Science Ltd. p. 1206. ISBN 0-7506-3365-4.
Jump up ^ MacKay, K. M.; MacKay, R. A.; Henderson, W. (2002). Introduction to Modern Inorganic Chemistry (6th ed.). Cheltenham: Nelson Thornes. pp. 194–196, 385. ISBN 0-7487-6420-8.
Jump up ^ Siegfried, R. (2002). From elements to atoms a history of chemical composition. Philadelphia, Pennsylvania: Library of Congress Cataloging-in-Publication Data. p. 92. ISBN 0-87169-924-9.
^ Jump up to: a b Ball, p. 100
Jump up ^ Horvitz, L. (2002). Eureka!: Scientific Breakthroughs That Changed The World. New York: John Wiley. p. 43. ISBN 978-0-471-23341-1. OCLC 50766822.
Jump up ^ Aug. Kekulé (1857). "Über die s. g. gepaarten Verbindungen und die Theorie der mehratomigen Radicale". Annalen der Chemie und Pharmacie. 104 (2): 129–150. doi:10.1002/jlac.18571040202.
Jump up ^ van Spronsen, J. W. (1969). The periodic system of chemical elements. Amsterdam: Elsevier. p. 19. ISBN 0-444-40776-6.
Jump up ^ "Alexandre-Emile Bélguier de Chancourtois (1820–1886)" (in French). Annales des Mines history page. Archived from the original on 27 November 2014. Retrieved 18 September 2014.
Jump up ^ Venable, pp. 85–86; 97
Jump up ^ Odling, W. (2002). "On the proportional numbers of the elements". Quarterly Journal of Science. 1: 642–648 (643).
^ Jump up to: a b Scerri, E. (2011). The periodic table: A very short introduction. Oxford: Oxford University Press. ISBN 978-0-19-958249-5.
Jump up ^ Kaji, M. (2004). "Discovery of the periodic law: Mendeleev and other researchers on element classification in the 1860s". In Rouvray, D. H.; King, R. Bruce. The periodic table: Into the 21st Century. Research Studies Press. pp. 91–122 (95). ISBN 0-86380-292-3.
Jump up ^ Newlands, J. A. R. (20 August 1864). "On Relations Among the Equivalents". Chemical News. 10: 94–95. Archived from the original on 1 January 2011.
Jump up ^ Newlands, J. A. R. (18 August 1865). "On the Law of Octaves". Chemical News. 12: 83. Archived from the original on 1 January 2011.
Jump up ^ Bryson, B. (2004). A Short History of Nearly Everything. Black Swan. pp. 141–142. ISBN 978-0-552-15174-0.
Jump up ^ Scerri 2007, p. 306
Jump up ^ Brock, W. H.; Knight, D. M. (1965). "The Atomic Debates: 'Memorable and Interesting Evenings in the Life of the Chemical Society'". Isis. The University of Chicago Press. 56 (1): 5–25. doi:10.1086/349922.
Jump up ^ Scerri 2007, pp. 87, 92
Jump up ^ Kauffman, G. B. (March 1969). "American forerunners of the periodic law". Journal of Chemical Education. 46 (3): 128–135 (132). Bibcode:1969JChEd..46..128K. doi:10.1021/ed046p128.
Jump up ^ Mendelejew, D. (1869). "Über die Beziehungen der Eigenschaften zu den Atomgewichten der Elemente". Zeitschrift für Chemie (in German): 405–406.
Jump up ^ Venable, pp. 96–97; 100–102
Jump up ^ Ball, pp. 100–102
Jump up ^ Pullman, B. (1998). The Atom in the History of Human Thought. Translated by Axel Reisinger. Oxford University Press. p. 227. ISBN 0-19-515040-6.
Jump up ^ Ball, p. 105
Jump up ^ Atkins, P. W. (1995). The Periodic Kingdom. HarperCollins Publishers, Inc. p. 87. ISBN 0-465-07265-8.
Jump up ^ Samanta, C.; Chowdhury, P. Roy; Basu, D. N. (2007). "Predictions of alpha decay half-lifes of heavy and superheavy elements". Nucl. Phys. A. 789: 142–154. arXiv:nucl-th/0703086  . Bibcode:2007NuPhA.789..142S. doi:10.1016/j.nuclphysa.2007.04.001.
Jump up ^ Scerri 2007, p. 112
Jump up ^ Kaji, M. (2002). "D. I. Mendeleev's Concept of Chemical Elements and the Principle of Chemistry" (PDF). Bull. Hist. Chem. 27 (1): 4–16. Archived (PDF) from the original on 6 July 2016.
Jump up ^ Adloff, J-P.; Kaufman, G. B. (25 September 2005). "Francium (Atomic Number 87), the Last Discovered Natural Element". The Chemical Educator. Archived from the original on 4 June 2013. Retrieved 26 March 2007.
Jump up ^ Hoffman, D. C.; Lawrence, F. O.; Mewherter, J. L.; Rourke, F. M. (1971). "Detection of Plutonium-244 in Nature". Nature. 234 (5325): 132–134. Bibcode:1971Natur.234..132H. doi:10.1038/234132a0. Archived from the original on 23 June 2011.
Jump up ^ Gray, p. 12
Jump up ^ Deming, H. G. (1923). General chemistry: An elementary survey. New York: J. Wiley & Sons. pp. 160, 165.
Jump up ^ Abraham, M.; Coshow, D.; Fix, W. Periodicity:A source book module, version 1.0 (PDF). New York: Chemsource, Inc. p. 3. Archived from the original (PDF) on 14 May 2012.
Jump up ^ Emsley, J. (7 March 1985). "Mendeleyev's dream table". New Scientist: 32–36(36).
Jump up ^ Fluck, E. (1988). "New notations in the period table". Pure and Applied Chemistry. 60 (3): 431–436 (432). doi:10.1351/pac198860030431.
Jump up ^ Ball, p. 111
Jump up ^ Scerri 2007, pp. 270‒71
Jump up ^ Masterton, W. L.; Hurley, C. N.; Neth, E. J. Chemistry: Principles and reactions (7th ed.). Belmont, CA: Brooks/Cole Cengage Learning. p. 173. ISBN 1-111-42710-0.
Jump up ^ Ball, p. 123
Jump up ^ Barber, R. C.; Karol, P. J.; Nakahara, Hiromichi; Vardaci, Emanuele; Vogt, E. W. (2011). "Discovery of the elements with atomic numbers greater than or equal to 113 (IUPAC Technical Report)". Pure Appl. Chem. 83 (7): 1485. doi:10.1351/PAC-REP-10-05-01.
Jump up ^ Эксперимент по синтезу 117-го элемента получает продолжение [Experiment on synthesis of the 117th element is to be continued] (in Russian). JINR. 2012. Archived from the original on 1 August 2013.
Jump up ^ Scerri, Eric (2013). "Element 61—Promethium". A Tale of 7 Elements. New York: Oxford University Press (USA). pp. 175–194(190). ISBN 978-0-19-539131-2. Archived from the original on 10 September 2017. ... no interruptions in the sequence of increasing atomic numbers ...
Jump up ^ Newell, S. B. (1980). Chemistry: An introduction. Boston: Little, Brown and Company. p. 196. ISBN 978-0-316-60455-0. Retrieved 27 August 2016.
Jump up ^ Jensen, W. B. (1982). "Classification, Symmetry and the Periodic Table". Computers & Mathematics with Applications. 12B (1/2): 487–510(498). doi:10.1016/0898-1221(86)90167-7.
Jump up ^ Leach, M. R. (2012). "Concerning electronegativity as a basic elemental property and why the periodic table is usually represented in its medium form". Foundations of Chemistry. 15 (1): 13–29. doi:10.1007/s10698-012-9151-3.
Jump up ^ Thyssen, P.; Binnemans, K. (2011). Gschneidner Jr., K. A.; Bünzli, J-C.G; Vecharsky, Bünzli, eds. Accommodation of the Rare Earths in the Periodic Table: A Historical Analysis. Handbook on the Physics and Chemistry of Rare Earths. 41. Amsterdam: Elsevier. p. 76. ISBN 978-0-444-53590-0.
^ Jump up to: a b Scerri 2007, p. 20
Jump up ^ "Weird Words of Science: Lemniscate Elemental Landscapes". Fields of Science. fieldofscience.com. 22 March 2009. Archived from the original on 4 March 2016. Retrieved 4 January 2016.
Jump up ^ Emsely, J.; Sharp, R. (21 June 2010). "The periodic table: Top of the charts". The Independent. Archived from the original on 1 July 2017.
Jump up ^ Seaborg, G. (1964). "Plutonium: The Ornery Element". Chemistry. 37 (6): 14.
Jump up ^ Mark R. Leach. "1925 Courtines' Periodic Classification". Archived from the original on 16 May 2016. Retrieved 16 October 2012.
Jump up ^ Mark R. Leach. "1949 Wringley's Lamina System". Archived from the original on 3 December 2011. Retrieved 16 October 2012.
Jump up ^ Mazurs, E. G. (1974). Graphical Representations of the Periodic System During One Hundred Years. Alabama: University of Alabama Press. p. 111. ISBN 978-0-8173-3200-6.
Jump up ^ Mark R. Leach. "1996 Dufour's Periodic Tree". Archived from the original on 18 April 2010. Retrieved 16 October 2012.
Jump up ^ Mark R. Leach. "1989 Physicist's Periodic Table by Timothy Stowe". Archived from the original on 5 June 2012. Retrieved 16 October 2012.
Jump up ^ Bradley, D. (20 July 2011). "At last, a definitive periodic table?". ChemViews Magazine. doi:10.1002/chemv.201000107. Archived from the original on 1 May 2013.
Jump up ^ Scerri 2007, pp. 285‒86
Jump up ^ Scerri 2007, p. 285
Jump up ^ Mark R. Leach. "2002 Inorganic Chemist's Periodic Table". Archived from the original on 9 March 2013. Retrieved 16 October 2012.
Jump up ^ Scerri, E. (2008). "The role of triads in the evolution of the periodic table: Past and present". Journal of Chemical Education. 85 (4): 585–89 (see p.589). Bibcode:2008JChEd..85..585S. doi:10.1021/ed085p585.
Jump up ^ Alper, R. (2010). "The simplified periodic table: elements ordered by their subshells". The Journal of Biological Physics and Chemistry. 10 (2): 74–80. doi:10.4024/43AL09F.jbpc.10.02.
^ Jump up to: a b Scerri, E. (2012). "Some comments on the recently proposed periodic table featuring elements ordered by their subshells". Journal of Biological Physics and Chemistry. 12 (2): 69–70.
Jump up ^ Bent, H. A.; Weinhold, F. (2007). "Supporting information: News from the periodic table: An introduction to "Periodicity symbols, tables, and models for higher-order valency and donor–acceptor kinships"". Journal of Chemical Education. 84 (7): 3–4. doi:10.1021/ed084p1145.
Jump up ^ Francl, M. (May 2009). "Table manners" (PDF). Nature Chemistry. 1 (2): 97–98. Bibcode:2009NatCh...1...97F. doi:10.1038/nchem.183. PMID 21378810. Archived (PDF) from the original on 25 October 2012.
Jump up ^ IUPAC (1 May 2013). "IUPAC Periodic Table of the Elements" (PDF). iupac.org. IUPAC. Archived (PDF) from the original on 22 August 2015. Retrieved 20 September 2015.
Jump up ^ Seaborg, G. (1945). "The chemical and radioactive properties of the heavy elements". Chemical English Newspaper. 23 (23): 2190–2193.
Jump up ^ Cronyn, M. W. (August 2003). "The Proper Place for Hydrogen in the Periodic Table". Journal of Chemical Education. 80 (8): 947–951. Bibcode:2003JChEd..80..947C. doi:10.1021/ed080p947.
Jump up ^ Greenwood & Earnshaw, throughout the book
Jump up ^ Lewars, Errol G. (5 December 2008). Modeling Marvels: Computational Anticipation of Novel Molecules. Springer Science & Business Media. pp. 69–71. ISBN 978-1-4020-6973-4. Archived from the original on 19 May 2016.
Jump up ^ Thyssen, P.; Binnemans, K. (2011). Gschneidner Jr., K. A.; Bünzli, J-C.G; Vecharsky, Bünzli, eds. Accommodation of the Rare Earths in the Periodic Table: A Historical Analysis. Handbook on the Physics and Chemistry of Rare Earths. 41. Amsterdam: Elsevier. pp. 1–94. ISBN 978-0-444-53590-0.
Jump up ^ Hevesy, G. (1929). Redkie zemeli s tochki zreniya stroeniya atoma [Rare earths from the point of view of structure of atom] (cited in Trifonov 1970, p. 188) (in Russian). Leningrad: NKhTI.
Jump up ^ Stewart, P. J. (2008). "The Flyleaf Table: An Alternative". Journal of Chemical Education. 85 (11): 1490. Bibcode:2008JChEd..85.1490S. doi:10.1021/ed085p1490.
Jump up ^ Thyssen, P.; Binnemanns, K. (2011). "1: Accommodation of the rare earths in the periodic table: A historical analysis". In Gschneidner Jr., K. A.; Büzli, J-C. J.; Pecharsky, V. K. Handbook on the Physics and Chemistry of Rare Earths. 41. Amsterdam: Elsevier. pp. 80–81. ISBN 978-0-444-53590-0.
Jump up ^ Keeler, J.; Wothers, P. (2014). Chemical Structure and Reactivity: An Integrated Approach. Oxford: Oxford University. p. 259. ISBN 978-0-19-960413-5.
Jump up ^ Scerri, E. (2012). "Mendeleev's Periodic Table Is Finally Completed and What To Do about Group 3?". Chemistry International. 34 (4). doi:10.1515/ci.2012.34.4.28. Archived from the original on 10 September 2017.
Jump up ^ Castelvecchi, D. (8 April 2015). "Exotic atom struggles to find its place in the periodic table". Nature News. Archived from the original on 5 October 2015. Retrieved 20 September 2015.
Jump up ^ "The constitution of group 3 of the periodic table". IUPAC. 2015. Archived from the original on 5 July 2016. Retrieved 30 July 2016.
Jump up ^ Emsley, J. (2011). Nature's Building Blocks (new ed.). Oxford: Oxford University. p. 651. ISBN 978-0-19-960563-7.
^ Jump up to: a b c d e f g William B. Jensen (1982). "The Positions of Lanthanum (Actinium) and Lutetium (Lawrencium) in the Periodic Table". J. Chem. Educ. 59 (8): 634–636. Bibcode:1982JChEd..59..634J. doi:10.1021/ed059p634.
Jump up ^ Trifonov, D. N. (1970). Rare-earth elements and their position in the periodic system (translated from Russian). New Delhi: Indian National Scientific Documentation Centre. pp. 201–202.
Jump up ^ Greenwood, N. N.; Harrington, T. J. (1973). The chemistry of the transition elements. Oxford: Clarendon Press. p. 50. ISBN 0-19-855435-4.
Jump up ^ Aylward, G.; Findlay, T. (2008). SI chemical data (6th ed.). Milton, Queensland: John Wiley & Sons. ISBN 978-0-470-81638-7.
Jump up ^ Wiberg, N. (2001). Inorganic Chemistry. San Diego: Academic Press. p. 119. ISBN 0-12-352651-5.
Jump up ^ Wulfsberg, G. (2006). "Periodic table: Trends in the properties of the elements". Encyclopedia of Inorganic Chemistry. New York: John Wiley & Sons. p. 3. ISBN 978-0-470-86210-0.
^ Jump up to: a b Cotton, S. (2007). Lanthanide and Actinide Chemistry. Chichester: John Wiley & Sons. p. 150. ISBN 978-0-470-01006-8.
Jump up ^ Scerri, E. (15 September 2015). "Five ideas in chemical education that must die – Group three". Education in Chemistry. Royal Society of Chemistry. Archived from the original on 23 December 2015. Retrieved 19 September 2015. It is high time that the idea of group 3 consisting of Sc, Y, La and Ac is abandoned
Jump up ^ Jensen, W. B. (2015). "Some Comments on the Position of Lawrencium in the Periodic Table" (PDF). Archived from the original (PDF) on 23 December 2015. Retrieved 20 Sep 2015.
Jump up ^ Xu, W-H.; Pyykkö, P. (2016). "Is the chemistry of lawrencium peculiar?". Physical Chemistry Chemical Physics. 18 (26): 17351–17355. Bibcode:2016PCCP...1817351X. doi:10.1039/C6CP02706G.
Jump up ^ King, R. B. (1995). Inorganic Chemistry of Main Group Elements. New York: Wiley-VCH. p. 289. ISBN 1-56081-679-1.
Jump up ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "transition element".
Jump up ^ Xuefang, W.; Andrews, L.; Riedel, S.; Kaupp, M. (2007). "Mercury Is a Transition Metal: The First Experimental Evidence for HgF4". Angew. Chem. Int. Ed. 46 (44): 8371–8375. doi:10.1002/anie.200703710. PMID 17899620.
^ Jump up to: a b Jensen, W. B. (2008). "Is Mercury Now a Transition Element?". J. Chem. Educ. 85 (9): 1182–1183. Bibcode:2008JChEd..85.1182J. doi:10.1021/ed085p1182.
Jump up ^ Rayner-Canham, G.; Overton, T. Descriptive inorganic chemistry (4th ed.). New York: W H Freeman. pp. 484–485. ISBN 0-7167-8963-9.
Jump up ^ Schändel, M. (2003). The Chemistry of Superheavy Elements. Dordrecht: Kluwer Academic Publishers. p. 277. ISBN 1-4020-1250-0.
Jump up ^ Yakushev, Alexander; Eichler, Robert (2016). Gas-phase chemistry of element 114, flerovium (PDF). Nobel Symposium NS160 – Chemistry and Physics of Heavy and Superheavy Elements. doi:10.1051/epjconf/201613107003.
Jump up ^ Fricke, B.; Greiner, W.; Waber, J. T. (1971). "The continuation of the periodic table up to Z = 172. The chemistry of superheavy elements". Theoretica chimica acta. Springer-Verlag. 21 (3): 235–260. doi:10.1007/BF01172015.
Jump up ^ Frazier, K. (1978). "Superheavy Elements". Science News. 113 (15): 236–238. doi:10.2307/3963006. JSTOR 3963006.
Jump up ^ Pyykkö, P. (2011). "A suggested periodic table up to Z ≤ 172, based on Dirac–Fock calculations on atoms and ions". Physical Chemistry Chemical Physics. 13 (1): 161–168. Bibcode:2011PCCP...13..161P. doi:10.1039/c0cp01575j. PMID 20967377.
Jump up ^ Elliot, Q. A. (1911). "A modification of the periodic table". Journal of the American Chemical Society. 33 (5): 684–688 (688). doi:10.1021/ja02218a004.
Jump up ^ Seaborg, G. (c. 2006). "transuranium element (chemical element)". Encyclopædia Britannica. Archived from the original on 30 November 2010. Retrieved 16 March 2010.
Jump up ^ Cwiok, S.; Heenen, P.-H.; Nazarewicz, W. (2005). "Shape coexistence and triaxiality in the superheavy nuclei". Nature. 433 (7027): 705–9. Bibcode:2005Natur.433..705C. doi:10.1038/nature03336. PMID 15716943.
^ Jump up to: a b Ball, P. (November 2010). "Would Element 137 Really Spell the End of the Periodic Table? Philip Ball Examines the Evidence". Chemistry World. Royal Society of Chemistry. Archived from the original on 21 October 2012. Retrieved 30 September 2012.
Jump up ^ Eisberg, R.; Resnick, R. (1985). Quantum Physics of Atoms, Molecules, Solids, Nuclei and Particles. Wiley.
Jump up ^ Bjorken, J. D.; Drell, S. D. (1964). Relativistic Quantum Mechanics. McGraw-Hill.
Jump up ^ Greiner, W.; Schramm, S. (2008). "Resource Letter QEDV-1: The QED vacuum". American Journal of Physics. 76 (6): 509. Bibcode:2008AmJPh..76..509G. doi:10.1119/1.2820395. , and references therein.
^ Jump up to: a b Scerri, Eric (9 August 2013). "Is there an optimal periodic table and other bigger questions in the philosophy of science". ericscerri23.blogspot.com.au. Eric Scerri. Archived from the original on 13 June 2017. Retrieved 4 September 2013.
Jump up ^ Sella, Andrea (7 August 2013). "An elementary history lesson". New Scientist (2929). Archived from the original on 3 July 2016. Retrieved 13 June 2017.
Bibliography
Ball, P. (2002). The Ingredients: A Guided Tour of the Elements. Oxford: Oxford University Press. ISBN 978-0-19-284100-1.
Chang, R. (2002). Chemistry (7th ed.). New York: McGraw-Hill Higher Education. ISBN 978-0-19-284100-1.
Gray, T. (2009). The Elements: A Visual Exploration of Every Known Atom in the Universe. New York: Black Dog & Leventhal Publishers. ISBN 978-1-57912-814-2.
Greenwood, N. N.; Earnshaw, A. (1984). Chemistry of the Elements. Oxford: Pergamon Press. ISBN 978-0-08-022057-4.
Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Principles of structure and reactivity (4th ed.). New York: Harper Collins College Publishers. ISBN 978-0-06-042995-9.
Moore, J. T. (2003). Chemistry For Dummies. For Dummies (1st ed.). New York: Wiley Publications. ISBN 978-0-7645-5430-8.
Scerri, E. (2007). The periodic table: Its story and its significance. Oxford: Oxford University Press. ISBN 978-0-19-530573-9.
Scerri, E. (2011). The periodic table: A very short introduction. Oxford: Oxford University Press. ISBN 978-0-19-958249-5.
Venable, F. P. (1896). The Development of the Periodic Law. Easton, Pennsylvania: Chemical Publishing Company. OCLC 776059614.
Further reading
Emsley, J. (2011). "The Periodic Table". Nature's Building Blocks: An A-Z Guide to the Elements (New ed.). Oxford: Oxford University Press. pp. 634–651. ISBN 978-0-19-960563-7.
Mazurs, E. G. (1974). Graphical Representations of the Periodic System During One Hundred Years. Alabama: University of Alabama Press. ISBN 978-0-19-960563-7.
Rouvray, D.H.; King, R. B. (eds) (2004). The Periodic Table: Into the 21st Century. Proceedings of the 2nd International Conference on the Periodic Table, part 1, Kananaskis Guest Ranch, Alberta, 14−20 July 2003. Baldock, Hertfordshire: Research Studies Press. ISBN 978-0-86380-292-8. CS1 maint: Extra text: authors list (link)
Rouvray, D.H.; King, R. B. (eds) (2006). The Mathematics of the Periodic Table. Proceedings of the 2nd International Conference on the Periodic Table, part 2, Kananaskis Guest Ranch, Alberta, 14−20 July 2003. New York: Nova Science. ISBN 978-1-59454-259-6. CS1 maint: Extra text: authors list (link)
Scerri, E (n.d.). "Books on the Elements and the Periodic Table" (PDF). Retrieved 9 July 2018.
Scerri, E.; Restrepo, G (eds) (2018). Mendeleev to Oganesson: A Multidisciplinary Perspective on the Periodic Table. Proceedings of the 3rd International Conference on the Periodic Table, Cuzco, Peru 14−16 August 2012. Oxford: Oxford University Press. ISBN 978-0-86380-292-8. CS1 maint: Extra text: authors list (link)
van Spronsen, J. W. (1969). The Periodic System of Chemical Elements: A History of the First Hundred Years. Amsterdam: Elsevier. ISBN 978-0-444-40776-4.
Verde, M. (ed.) (1971). Atti del convegno Mendeleeviano: Periodicità e simmetrie nella struttura elementare della materia [Proceedings of the Mendeleevian conference: Periodicity and symmetry in the elementary structure of matter]. 1st International Conference on the Periodic Table, Torino-Roma, 15−21 September 1969. Torino: Accademia delle Scienze di Torino. CS1 maint: Extra text: authors list (link)
External links
Find more aboutPeriodic tableat Wikipedia's sister projects
Definitions from Wiktionary
Media from Wikimedia Commons
News from Wikinews
Quotations from Wikiquote
Texts from Wikisource
Textbooks from Wikibooks
Learning resources from Wikiversity
Periodic table on the IUPAC web site, noting there is no official IUPAC table
Dynamic periodic table, with interactive layouts
Eric Scerri, leading philosopher of science specializing in the history and philosophy of the periodic table
The INTERNET Database of Periodic Tables
Periodic table of endangered elements
Periodic table of samples
Periodic table of videos
WebElements
hide
v
t
e
Periodic table (Large cells)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
1
H He
2
Li Be B C N O F Ne
3
Na Mg Al Si P S Cl Ar
4
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
5
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
6
Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
7
Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
Alkali metal Alkaline earth metal Lanthanide Actinide Transition metal Post-transition metal Metalloid Reactive nonmetal Noble gas Unknown
chemical
properties
show
v
t
e
Periodic table
Periodic table forms
Standard
18-column
18-column, large cells
32-column, large cells
Alternative
Alternatives
Janet's left step table
Extended
Extension beyond the 7th period
Aufbau
Fricke
Pyykkö
Sets of elements
By periodic table structure
Groups
1 (Alkali metals)
2 (Alkaline earth metals)
3
4
5
6
7
8
9
10
11
12
13
14
15 (Pnictogens)
16 (Chalcogens)
17 (Halogens)
18 (Noble gases)
Periods
1
2
3
4
5
6
7
8+
Aufbau
Fricke
Pyykkö
Blocks
s-block
p-block
d-block
f-block
g-block
Aufbau principle
By metallicity
Metals
Alkali metals
Alkaline earth metals
Lanthanides
Actinides
Transition metals
Post-transition metals
Metalloids
Lists of metalloids by source
Dividing line
Nonmetals
Reactive nonmetals
Noble gases
Other sets
Nutritional elements
Platinum-group metals (PGM)
Rare-earth elements
Refractory metals
Precious metals
Coinage metals
Noble metal
Heavy metals
Native metals
Transuranium elements
Transactinide elements
Major actinides
Minor actinides
Elements
Lists
By: Abundance (in humans)
Atomic properties
Nuclear stability
Production
Symbol
Properties
Atomic weight
Crystal structure
Electron affinity
Electron configuration
Electronegativity
Allen
Pauling
Goldschmidt classification
Maximum valence
Data pages
Abundance
Atomic radius
Boiling point
Critical point
Density
Elasticity
Electrical resistivity
Electron affinity
Electron configuration
Electronegativity
Hardness
Heat capacity
Heat of fusion
Heat of vaporization
Ionization energy
Melting point
Oxidation state
Speed of sound
Thermal conductivity
Thermal expansion coefficient
Vapor pressure
History
Element discoveries
Mendeleev's predictions
Naming
etymology
controversies
for places
for people
in East Asia
See also
IUPAC
nomenclature
systematic element name
Trivial name
Dmitri Mendeleev
Book
Category
Chemistry Portal
show
v
t
e
Branches of chemistry
Dictionary of chemical formulas
List of biomolecules
List of inorganic compounds
Periodic table
Physical
Chemical kinetics
Chemical physics
Nuclear chemistry
Electrochemistry
Femtochemistry
Geochemistry
Photochemistry
Quantum chemistry
Solid-state chemistry
Spectroscopy
Surface science
Thermochemistry
Organic
Biochemistry
Bioorganic chemistry
Biophysical chemistry
Chemical biology
Clinical chemistry
Fullerene chemistry
Medicinal chemistry
Neurochemistry
Pharmacy
Physical organic chemistry
Polymer chemistry
Inorganic
Bioinorganic chemistry
Cluster chemistry
Coordination chemistry
Materials science
Organometallic chemistry
Others
Actinide chemistry
Analytical chemistry
Astrochemistry
Atmospheric chemistry
Chemistry education
Clay chemistry
Click chemistry
Computational chemistry
Cosmochemistry
Environmental chemistry
Food chemistry
Forensic chemistry
Green chemistry
Ocean chemistry
Post-mortem chemistry
Supramolecular chemistry
Theoretical chemistry
Wet chemistry
Category
Commons
WikiProject
Authority control
WorldCat Identities
BNE: XX532419
BNF: cb122746941 (data)
GND: 4125872-1
LCCN: sh85099885
VIAF: 186605590
Retrieved from "https://en.wikipedia.org/w/index.php?title=Periodic_table&oldid=853864342"
Categories:
Periodic table
Chemical elements
Classification systems
Dmitri Mendeleev
Russian inventions
1869 works
Hidden categories:
CS1 French-language sources (fr)
CS1: Julian–Gregorian uncertainty
CS1 German-language sources (de)
CS1 uses Russian-language script (ru)
CS1 Russian-language sources (ru)
Wikipedia indefinitely semi-protected pages
Articles containing potentially dated statements from 2016
All articles containing potentially dated statements
CS1 maint: Extra text: authors list
Use dmy dates from June 2015
Featured articles
Wikipedia articles with BNE identifiers
Wikipedia articles with BNF identifiers
Wikipedia articles with GND identifiers
Wikipedia articles with LCCN identifiers
Wikipedia articles with VIAF identifiers
Navigation menu
Personal tools
Not logged in
Talk
Contributions
Create account
Log in
Namespaces
Article
Talk
Variants
Views
Read
View source
View history
More
Search
Navigation
Main page
Contents
Featured content
Current events
Random article
Donate to Wikipedia
Wikipedia store
Interaction
Help
About Wikipedia
Community portal
Recent changes
Contact page
Tools
What links here
Related changes
Upload file
Special pages
Permanent link
Page information
Wikidata item
Cite this page
Print/export
Create a book
Download as PDF
Printable version
In other projects
Wikimedia Commons
Wikibooks
Wikiversity
Languages
Acèh
Afrikaans
Alemannisch
አማርኛ
Аҧсшәа
العربية
Aragonés
Armãneashti
অসমীয়া
Asturianu
Avañe'ẽ
Azərbaycanca
تۆرکجه
বাংলা
Bân-lâm-gú
Башҡортса
Беларуская
Беларуская (тарашкевіца)
भोजपुरी
Български
Boarisch
བོད་ཡིག
Bosanski
Brezhoneg
Буряад
Català
Чӑвашла
Cebuano
Čeština
ChiShona
Cymraeg
Dansk
Deutsch
ދިވެހިބަސް
Eesti
Ελληνικά
Español
Esperanto
Estremeñu
Euskara
فارسی
Fiji Hindi
Føroyskt
Français
Frysk
Furlan
Gaeilge
Gaelg
Gàidhlig
Galego
贛語
Gĩkũyũ
ગુજરાતી
客家語/Hak-kâ-ngî
한국어
Հայերեն
हिन्दी
Hrvatski
Ido
Ilokano
বিষ্ণুপ্রিয়া মণিপুরী
Bahasa Indonesia
Interlingua
Ирон
Íslenska
Italiano
עברית
Basa Jawa
ಕನ್ನಡ
Kapampangan
ქართული
Қазақша
Kiswahili
Коми
Kreyòl ayisyen
Kurdî
Кыргызча
Лезги
ລາວ
لۊری شومالی
Latina
Latviešu
Lëtzebuergesch
Lietuvių
Limburgs
Lingála
La .lojban.
Lumbaart
Magyar
Македонски
Malagasy
മലയാളം
Malti
Māori
मराठी
მარგალური
مصرى
Bahasa Melayu
Baso Minangkabau
Mìng-dĕ̤ng-ngṳ̄
Mirandés
Монгол
မြန်မာဘာသာ
Nāhuatl
Nederlands
नेपाली
नेपाल भाषा
日本語
Nordfriisk
Norsk
Norsk nynorsk
Occitan
Олык марий
ଓଡ଼ିଆ
Oʻzbekcha/ўзбекча
ਪੰਜਾਬੀ
پنجابی
Papiamentu
Patois
Перем Коми
ភាសាខ្មែរ
Picard
Piemontèis
Tok Pisin
Plattdüütsch
Polski
Ποντιακά
Português
Română
Runa Simi
Русиньскый
Русский
Саха тыла
Sardu
Scots
Seeltersk
Sesotho
Shqip
Sicilianu
සිංහල
Simple English
Slovenčina
Slovenščina
Soomaaliga
کوردی
Sranantongo
Српски / srpski
Srpskohrvatski / српскохрватски
Basa Sunda
Suomi
Svenska
Tagalog
தமிழ்
Tarandíne
Татарча/tatarça
తెలుగు
ไทย
Тоҷикӣ
Türkçe
Türkmençe
Українська
اردو
ئۇيغۇرچە / Uyghurche
Vèneto
Vepsän kel’
Tiếng Việt
Võro
Walon
文言
West-Vlams
Winaray
吴语
ייִדיש
Yorùbá
粵語
Zazaki
Žemaitėška
中文
169 more
Edit links
This page was last edited on 7 August 2018, at 12:49 (UTC).
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.
Privacy policy
About Wikipedia
Disclaimers
Contact Wikipedia
Developers
Cookie statement
Mobile view
Enable previews

key: html

type: local

value: div

attrs: id class

values: mw-page-base noprint

values: mw-head-base noprint

value: a

value: img

attrs: alt src width height srcset data-file-width data-file-height

values: This is a featured article. Click here for more information.

attrs: href title

values: mw-indicator-featured-star mw-indicator

values: mw-indicator-pp-default mw-indicator

attrs: id class lang

values: firstHeading firstHeading en

values: siteSub noprint

attrs: class href

values: mw-jump-link #mw-head

values: mw-jump-link #p-search

attrs: href class title

values:
/wiki/Periodic_table_(disambiguation)
mw-disambig
Periodic table (disambiguation)

values:
note
hatnote navigation-not-searchable

value: p

attrs: alt src width height class srcset data-file-width data-file-height

attrs: href class

attrs: class style

values:
/wiki/Fricke_model
mw-redirect
Fricke model

values:
/wiki/Pyykk%C3%B6_model
mw-redirect
Pyykkö model

values: font-size: 105%; padding: 0.2em 0px 0.4em; text-align: center; display: none;

values: Timeline of chemical element discoveries

values: List of chemical element name etymologies

values: List of places used in the names of chemical elements

values: List of people whose names are used in chemical element names

values: List of chemical elements naming controversies

values: Chemical elements in East Asian languages

values: padding:0 0.1em 0.4em;border-top:1px solid #aaa; text-align:left; background:#eeeeff;

values: Properties of metals, metalloids and nonmetals

values: Dividing line between metals and nonmetals

values:
/wiki/Reactive_nonmetal
mw-redirect
Reactive nonmetal

values:
/wiki/Transplutonium_element
mw-redirect
Transplutonium element

values: List of elements by stability of isotopes

values: List of world production chemical elements

values:
/wiki/Atomic_weight
mw-redirect
Atomic weight

values: Atomic radii of the elements (data page)

values: Boiling points of the elements (data page)

values: Critical points of the elements (data page)

values: Elastic properties of the elements (data page)

values: Electrical resistivities of the elements (data page)

values: Electron configurations of the elements (data page)

values: Electronegativities of the elements (data page)

values: Heat capacities of the elements (data page)

values: Heats of fusion of the elements (data page)

values: Heats of vaporization of the elements (data page)

values: Ionization energies of the elements (data page)

values: Melting points of the elements (data page)

values: List of oxidation states of the elements

values: Speeds of sound of the elements (data page)

values: Thermal conductivities of the elements (data page)

values: Thermal expansion coefficients of the elements (data page)

values: Vapor pressures of the elements (data page)

values: padding:0 0.1em 0.4em;border-top:1px solid #aaa; border-bottom:1px solid #aaa; background:#eeeeff;

values: float:right;clear:right;width:22.0em;margin:0 0 1.0em 1.0em;background:#f9f9f9;border:1px solid #aaa;padding:0.2em;border-spacing:0.4em 0;text-align:center;line-height:1.4em;font-size:88%

values:
/wiki/Periodic_table_period
mw-redirect
Periodic table period

values:
/wiki/Element_discovery
mw-redirect
Element discovery

values:
/wiki/Chemical_reactions
mw-redirect
Chemical reactions

values: checkbox button toctogglecheckbox toctogglecheckbox display:none

values:
plainlinks hlist navbar mini
float:left; text-align:left

values: display:block; color:black; font-size:85%; height:2.2em; line-height:1.1em; vertical-align:top;

values: display:block; color:black; font-size:85%; height:1.1em; line-height:1.1em;

values: Hydrogen: reactive nonmetal; primordial; gas

values: background: #f0ff8f; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: background: #c0ffff; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Lithium: alkali metal; primordial; solid

values: background: #ff6666; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Beryllium: alkaline earth metal; primordial; solid

values: background: #ffdead; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: background: #cccc99; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Carbon: reactive nonmetal; primordial; solid

values: Nitrogen: reactive nonmetal; primordial; gas

values: Oxygen: reactive nonmetal; primordial; gas

values: Fluorine: reactive nonmetal; primordial; gas

values: Magnesium: alkaline earth metal; primordial; solid

values: Aluminium: post-transition metal; primordial; solid

values: background: #cccccc; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Phosphorus: reactive nonmetal; primordial; solid

values: Sulfur: reactive nonmetal; primordial; solid

values: Chlorine: reactive nonmetal; primordial; gas

values: Potassium: alkali metal; primordial; solid

values: Calcium: alkaline earth metal; primordial; solid

values: Scandium: transition metal; primordial; solid

values: background: #ffc0c0; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Titanium: transition metal; primordial; solid

values: Vanadium: transition metal; primordial; solid

values: Chromium: transition metal; primordial; solid

values: Manganese: transition metal; primordial; solid

values: Iron: transition metal; primordial; solid

values: Cobalt: transition metal; primordial; solid

values: Nickel: transition metal; primordial; solid

values: Copper: transition metal; primordial; solid

values: Zinc: post-transition metal; primordial; solid

values: Gallium: post-transition metal; primordial; solid

values: Selenium: reactive nonmetal; primordial; solid

values: Bromine: reactive nonmetal; primordial; liquid

values: Rubidium: alkali metal; primordial; solid

values: Strontium: alkaline earth metal; primordial; solid

values: Yttrium: transition metal; primordial; solid

values: Zirconium: transition metal; primordial; solid

values: Niobium: transition metal; primordial; solid

values: Molybdenum: transition metal; primordial; solid

values: Technetium: transition metal; from decay; solid

values: background: #ffc0c0; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Ruthenium: transition metal; primordial; solid

values: Rhodium: transition metal; primordial; solid

values: Palladium: transition metal; primordial; solid

values: Silver: transition metal; primordial; solid

values: Cadmium: post-transition metal; primordial; solid

values: Indium: post-transition metal; primordial; solid

values: Tin: post-transition metal; primordial; solid

values: Iodine: reactive nonmetal; primordial; solid

values: Caesium: alkali metal; primordial; solid

values: Barium: alkaline earth metal; primordial; solid

values: Lanthanum: lanthanide; primordial; solid

values: background: #ffbfff; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Hafnium: transition metal; primordial; solid

values: Tantalum: transition metal; primordial; solid

values: Tungsten: transition metal; primordial; solid

values: Rhenium: transition metal; primordial; solid

values: Osmium: transition metal; primordial; solid

values: Iridium: transition metal; primordial; solid

values: Platinum: transition metal; primordial; solid

values: Gold: transition metal; primordial; solid

values: Mercury: post-transition metal; primordial; liquid

values: Thallium: post-transition metal; primordial; solid

values: Lead: post-transition metal; primordial; solid

values: Bismuth: post-transition metal; primordial; solid

values: Polonium: post-transition metal; from decay; solid

values: background: #cccccc; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: background: #cccc99; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: background: #c0ffff; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Francium: alkali metal; from decay; solid

values: background: #ff6666; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Radium: alkaline earth metal; from decay; solid

values: background: #ffdead; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: background: #ff99cc; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Rutherfordium: transition metal; synthetic; unknown phase

values: background: #ffc0c0; border-top: 2px dotted #6e6e8e; border-bottom: 2px dotted #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Dubnium: transition metal; synthetic; unknown phase

values: Seaborgium: transition metal; synthetic; unknown phase

values: Bohrium: transition metal; synthetic; unknown phase

values: Hassium: transition metal; synthetic; unknown phase

values: Meitnerium: unknown chemical properties; synthetic; unknown phase

values: background: #e8e8e8; border-top: 2px dotted #6e6e8e; border-bottom: 2px dotted #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Darmstadtium: unknown chemical properties; synthetic; unknown phase

values: Roentgenium: unknown chemical properties; synthetic; unknown phase

values: Copernicium: post-transition metal; synthetic; unknown phase

values: background: #cccccc; border-top: 2px dotted #6e6e8e; border-bottom: 2px dotted #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Nihonium: unknown chemical properties; synthetic; unknown phase

values: Flerovium: unknown chemical properties; synthetic; unknown phase

values: Moscovium: unknown chemical properties; synthetic; unknown phase

values: Livermorium: unknown chemical properties; synthetic; unknown phase

values: Tennessine: unknown chemical properties; synthetic; unknown phase

values: Oganesson: unknown chemical properties; synthetic; unknown phase

values: Praseodymium: lanthanide; primordial; solid

values: Neodymium: lanthanide; primordial; solid

values: Promethium: lanthanide; from decay; solid

values: background: #ffbfff; border-top: 2px dashed #6e6e8e; border-bottom: 2px dashed #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Gadolinium: lanthanide; primordial; solid

values: Dysprosium: lanthanide; primordial; solid

values: Ytterbium: lanthanide; primordial; solid

values: background: #ff99cc; border-top: 2px solid #6e6e8e; border-bottom: 2px solid #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Protactinium: actinide; from decay; solid

values: background: #ff99cc; border-top: 2px dotted #6e6e8e; border-bottom: 2px dotted #6e6e8e; display: block; line-height: 1.1em; overflow: hidden; padding: 2px 0; text-align: center; vertical-align: bottom;

values: Fermium: actinide; synthetic; unknown phase

values: Mendelevium: actinide; synthetic; unknown phase

values: Nobelium: actinide; synthetic; unknown phase

values: Lawrencium: actinide; synthetic; unknown phase

values: color: #cb0000;background: #e0e0e0;margin:0.2em; text-align:center; min-width:9em;; display: inline-block;

values: color: #000000;background: #e0e0e0;margin:0.2em; text-align:center; min-width:9em;; display: inline-block;

values: color: #007000;background: #e0e0e0;margin:0.2em; text-align:center; min-width:9em;; display: inline-block;

values: color: #606060;background: #e0e0e0;margin:0.2em; text-align:center; min-width:9em;; display: inline-block;

values: Standard conditions for temperature and pressure

values:
/wiki/Primordial_element
mw-redirect
Primordial element

values: text-align:center;display:inline-block; width:8em; border-top:2px solid #6e6e8e; border-bottom:2px solid #6e6e8e; background:#e0e0e0;

values: text-align:center;display:inline-block; width:8em; border-top:2px dashed #6e6e8e; border-bottom:2px dashed #6e6e8e; background:#e0e0e0;

values: text-align:center;display:inline-block; width:8em; border-top:2px dotted #6e6e8e; border-bottom:2px dotted #6e6e8e; background:#e0e0e0;

values: border-top: 1px solid #a2a9b1;padding:0.3em;

values: display: inline-block; vertical-align: top;

values: border-top: 1px solid #a2a9b1;padding:0.3em; text-align:left

values: border: 1px solid #a2a9b1; width:100%; line-height:120%; text-align:center; vertical-align:top; font-size:85%; background:#f8f8f8; margin:0; font-size:100%;

values: background:#f8f8f8; font-size:90%; border:1px solid #a9a9a9; width:100%; max-width:1800px; margin:0 auto; padding:2px; text-align:center; vertical-align:top;

values: plainlinks noexcerpt noprint asof-tag update

values: International Union of Pure and Applied Chemistry

values:
/wiki/Valence_shell
mw-redirect
Valence shell

values:
/wiki/Group_14_element
mw-redirect
Group 14 element

values:
/wiki/Group_10_elements
mw-redirect
Group 10 elements

values: Collective names of groups of like elements

values: Template talk:Periodic table (group names)

values: background:#e1e1e1; border-top:1px solid #b8b8b8; text-align:center;

values: background:#e1e1e1; border-top:1px solid #b8b8b8;

values:
/wiki/Alkali_metals
mw-redirect
Alkali metals

values:
/wiki/Alkaline_earth_metals
mw-redirect
Alkaline earth metals

values:
/wiki/Noble_gases
mw-redirect
Noble gases

values: text-align:center; color:#000000; background:#f0ff8f; border:none; ;

values: text-align:center; color:#000000; background:#c0ffff; border:none; ;

values: text-align:center; color:#000000; background:#ff6666; border:none; ;

values: text-align:center; color:#000000; background:#ffdead; border:none; ;

values: text-align:center; color:#000000; background:#cccc99; border:none; ;

values: text-align:center; color:#000000; background:#cccccc; border:none; ;

values: text-align:center; color:#000000; background:#ffc0c0; border:none; ;

values: text-align:center; color:#000000; background:#ff6666; border:none; min-width:4%;;

values: text-align:center; color:#000000; background:#ffdead; border:none; min-width:4%;;

values: text-align:center; color:#000000; background:#ffbfff; border:none; min-width:4%;;

values: font-size:95%; background:#ffbfff; padding:0 1px; width:*;

values: text-align:center; color:#000000; background:#ffc0c0; border:none; min-width:4%;;

values: text-align:center; color:#000000; background:#cccccc; border:none; min-width:4%;;

values: text-align:center; color:#000000; background:#cccc99; border:none; min-width:4%;;

values: text-align:center; color:#000000; background:#c0ffff; border:none; min-width:4%;;

values: text-align:center; color:#000000; background:#ff99cc; border:none; ;

values: font-size:95%; background:#ff99cc; padding:0 1px;

values: text-align:center; color:#000000; background:#e8e8e8; border:none; ;

values: Darmstadtium: unknown chemical properties

values: Roentgenium: unknown chemical properties

values: Livermorium: unknown chemical properties

values: display:block;overflow:auto;width:100%;text-align:center; max-width:1300px; margin:0; padding:0;

values: background:#f8f8f8; font-size:85%; border:1px solid #a9a9a9; width:100%; margin:0 auto; padding:2px; text-align:center; vertical-align:top;

values:
/wiki/Transition_metals
mw-redirect
Transition metals

values: display:inline-block; width:1.5em; height:1.5em; margin:1px 0; border:none; background-color:#eee8aa; color:black; font-size:100%; text-align:center;

values: display:inline-block; width:1.5em; height:1.5em; margin:1px 0; border:none; background-color:#cccc99; color:black; font-size:100%; text-align:center;

values: display:inline-block; width:1.5em; height:1.5em; margin:1px 0; border:none; background-color:#b0e0e6; color:black; font-size:100%; text-align:center;

values: display:inline-block; width:1.5em; height:1.5em; margin:1px 0; border:none; background-color:#e8e8e8; color:black; font-size:100%; text-align:center;

values:
/wiki/Noble_metals
mw-redirect
Noble metals

values:
/wiki/Electronic_configuration
mw-redirect
Electronic configuration

values:
/wiki/Madelung_rule
mw-redirect
Madelung rule

values:
/wiki/Relativistic_effect
mw-redirect
Relativistic effect

values:
/wiki/Valence_electrons
mw-redirect
Valence electrons

values:
/wiki/Group_11_elements
mw-redirect
Group 11 elements

values: background:#d8d8d8; padding:0.15em 0.3em; font-size:90%; line-height:110%; font-weight:bold;

values: display:block;width:6px;height:8px;overflow:hidden;padding:0;color:transparent;background-color:#c0ffff; border:1px solid black; margin:-1px;

values: display:block;width:6px;height:8px;overflow:hidden;padding:0;color:transparent;background-color:#ffc0c0; border:1px solid black; margin:-1px;

values: display:block;width:6px;height:8px;overflow:hidden;padding:0;color:transparent;background-color:#cccccc; border:1px solid black; margin:-1px;

values: display:block;width:6px;height:8px;overflow:hidden;padding:0;color:transparent;background-color:#ffbfff; border:1px solid black; margin:-1px;

values: display:block;width:6px;height:8px;overflow:hidden;padding:0;color:transparent;background-color:#ff99cc; border:1px solid black; margin:-1px;

values: empty-cells:hidden; border:none; padding:0; border-spacing:1px; border-collapse:separate; margin:0;

values: margin: 0.15em 0; background-color:transparent; margin:0; padding:0; text-align:center; border:none;

attrs: style role aria-labelledby aria-describedby

values: float: right; margin-left: 20px; font-size:85%; width:20em float:right; background:#f8f8f8; padding:0.3em; border:1px solid #a9a9a9; margin:0 0 0.25em 0.5em; text-align:center;;

values:
/wiki/Law_of_Octaves
mw-redirect
Law of Octaves

values:
/wiki/Atomic_weights
mw-redirect
Atomic weights

values:
/wiki/Transuranic_elements
mw-redirect
Transuranic elements

values:
/wiki/Element_naming_controversy
mw-redirect
Element naming controversy

values: Template talk:Periodic table (left step)

values: background:#d8d8d8; padding:2px 4px;font-weight:bold; text-align:center;

values: background: #ff9999;; display: inline-block;

values: background: #fdff8c;; display: inline-block;

values: background: #99ccff;; display: inline-block;

values: background: #9bff99;; display: inline-block;

values: height:7px; border-bottom:1px solid black

values: border-spacing:1px;display:block;overflow:auto;width:100%; text-align:center;border-collapse:separate!important;margin:0 0 0.5em 0!important;

values: background:#f8f8f8; font-size:90%; border:1px solid #a9a9a9; width:100%; max-width:1800px; margin:0 auto; padding:2px; vertical-align:top;

values: float:left; margin:3px 2px; background:black; width:2px; height:2px;

values: float:left; border-spacing:1px;; background:black; width:2px; height:2px; margin:3px 2px;

values: background-color:transparent; margin-top:0; border-top:0; padding:0; border-spacing:1px; border-collapse:separate;

values: float: right; margin-left: 20px; font-size:85%; float:right; background:#f8f8f8; padding:0.3em; border:1px solid #a9a9a9; margin:0 0 0.25em 0.5em; text-align:center;;

values:
/wiki/Period_8_element
mw-redirect
Period 8 element

values: display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle

values: margin:0.5em 0 0.5em 1em;border:solid #aaa 1px

values:
/wiki/Standard_model
mw-redirect
Standard model

values: -moz-column-width: 30em; -webkit-column-width: 30em; column-width: 30em;

values:
/wiki/Pauling_scale
mw-redirect
Pauling scale

values:
/wiki/Allen_scale
mw-redirect
Allen scale

values:
/wiki/Chemical_and_Engineering_News
mw-redirect
Chemical and Engineering News

values:
/wiki/P._W._Atkins
mw-redirect
P. W. Atkins

values:
nofollow
external text
//doi.org/10.1515/pac-2015-0305

values:
nofollow
external text
//doi.org/10.1351/pac200274050787

values:
nofollow
external text
//doi.org/10.1021/ba-1967-0071

values:
nofollow
external text
//doi.org/10.1351/pac198860030431

values:
nofollow
external text
//www.worldcat.org/oclc/52445586

values:
nofollow
external text
//www.worldcat.org/oclc/52047235

values:
nofollow
external text
//www.worldcat.org/oclc/220756597

values:
nofollow
external text
//www.worldcat.org/oclc/300468713

values:
nofollow
external text
http://goldbook.iupac.org/E01990.html

values: Journal of the American Chemical Society

values:
nofollow
external text
//doi.org/10.1021/ja01348a011

values:
nofollow
external text
//doi.org/10.1007/s11837-014-1247-x

values:
nofollow
external text
//doi.org/10.1038/nature14342

values:
/wiki/PubMed_Identifier
mw-redirect
PubMed Identifier

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/25855457

values:
nofollow
external text
//www.worldcat.org/oclc/50766822

values:
/wiki/Annalen_der_Chemie_und_Pharmacie
mw-redirect
Annalen der Chemie und Pharmacie

values:
nofollow
external text
//doi.org/10.1002/jlac.18571040202

values:
/wiki/The_University_of_Chicago_Press
mw-redirect
The University of Chicago Press

values:
nofollow
external text
//doi.org/10.1086/349922

values:
nofollow
external text
//doi.org/10.1021/ed046p128

values:
nofollow
external text
//arxiv.org/abs/nucl-th/0703086

attrs: alt src title width height srcset data-file-width data-file-height

values:
/wiki/Bull._Hist._Chem.
mw-redirect
Bull. Hist. Chem.

values:
nofollow
external text
//doi.org/10.1038/234132a0

values:
nofollow
external text
//doi.org/10.1351/PAC-REP-10-05-01

values:
nofollow
external text
//doi.org/10.1002/chemv.201000107

values:
nofollow
external text
//doi.org/10.1021/ed085p585

values:
nofollow
external text
//doi.org/10.4024/43AL09F.jbpc.10.02

values:
nofollow
external text
//doi.org/10.1021/ed084p1145

values:
nofollow
external text
//doi.org/10.1038/nchem.183

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/21378810

values:
nofollow
external text
//doi.org/10.1021/ed080p947

values:
nofollow
external text
//doi.org/10.1021/ed085p1490

values:
nofollow
external text
//doi.org/10.1515/ci.2012.34.4.28

values:
nofollow
external text
//doi.org/10.1021/ed059p634

values:
nofollow
external text
//doi.org/10.1039/C6CP02706G

values:
nofollow
external text
http://goldbook.iupac.org/T06456.html

values:
nofollow
external text
//doi.org/10.1002/anie.200703710

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/17899620

values:
nofollow
external text
//doi.org/10.1021/ed085p1182

values:
nofollow
external text
//doi.org/10.1051/epjconf/201613107003

values:
nofollow
external text
//doi.org/10.1007/BF01172015

values:
nofollow
external text
//doi.org/10.2307/3963006

values:
nofollow
external text
//www.jstor.org/stable/3963006

values:
nofollow
external text
//doi.org/10.1039/c0cp01575j

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/20967377

values:
nofollow
external text
//doi.org/10.1021/ja02218a004

values:
nofollow
external text
//doi.org/10.1038/nature03336

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/15716943

values:
nofollow
external text
//doi.org/10.1119/1.2820395

values: -moz-column-width: 30em; -webkit-column-width: 30em; column-width: 30em; list-style-type: decimal;

values:
nofollow
external text
//www.worldcat.org/oclc/776059614

values: Category:CS1 maint: Extra text: authors list

values: padding-bottom: 0.75em; text-align: center;

values: display: inline-block; width: 31px; line-height: 31px; vertical-align: middle; text-align: center;

values: display: inline-block; margin-left: 4px; width: 182px; vertical-align: middle;

values: border-top:1px solid #aaa; padding-top: 0.75em;

values: metadata plainlinks plainlist mbox-small

values: border:1px solid #aaa; padding:0.75em; background:#f9f9f9;

values:
nofollow
external text
http://www.ptable.com

values:
nofollow
http://ericscerri.com/
external text

values:
nofollow
http://www.periodictable.com/
external text

values:
nofollow
external text
http://www.periodicvideos.com

values:
nofollow
external text
http://www.webelements.com

values: Template:Periodic table (32 columns, compact)

values: Template talk:Periodic table (32 columns, compact)

values: text-align:center; background:#f0ff8f; border:none; ;

values: text-align:center; background:#c0ffff; border:none; ;

values: text-align:center; background:#ff6666; border:none; ;

values: text-align:center; background:#ffdead; border:none; ;

values: text-align:center; background:#cccc99; border:none; ;

values: text-align:center; background:#cccccc; border:none; ;

values: text-align:center; background:#ffc0c0; border:none; ;

values: text-align:center; background:#ffbfff; border:none; ;

values: text-align:center; background:#ff99cc; border:none; ;

values: Meitnerium, 109 (unknown chemical properties)

values: text-align:center; background:#e8e8e8; border:none; ;

values: Darmstadtium, 110 (unknown chemical properties)

values: Roentgenium, 111 (unknown chemical properties)

values: Copernicium, 112 (post-transition metal)

values: Nihonium, 113 (unknown chemical properties)

values: Flerovium, 114 (unknown chemical properties)

values: Moscovium, 115 (unknown chemical properties)

values: Livermorium, 116 (unknown chemical properties)

values: Tennessine, 117 (unknown chemical properties)

values: Oganesson, 118 (unknown chemical properties)

values:
0
table-layout:fixed; width:100%;
periodic-table-legend

values: padding:0em 0.25em border: 1px solid #a2a9b1; width:100%; line-height:120%; text-align:center; vertical-align:top; font-size:85%; background:#f8f8f8; margin:0; font-size:90%; margin-top:0.5em; padding:0.3em;

values: nowraplinks collapsible expanded navbox-inner mw-collapsible mw-made-collapsible

values:
/wiki/List_of_metalloid_lists
mw-redirect
List of metalloid lists

values: Template:Periodic table (nutritional elements)

values:
row
navbox-group
width:1%;white-space: normal;

values: Template:Periodic table (electron affinities)

values: Periodic table (electron configurations)

values: Template:Periodic table (electronegativity by Allen scale)

values: Template:Periodic table (electronegativity by Pauling scale)

values: nowraplinks hlist collapsible autocollapse navbox-inner mw-collapsible mw-made-collapsible mw-collapsed

values:
/wiki/Dictionary_of_chemical_formulas
mw-redirect
Dictionary of chemical formulas

values:
*_Dictionary_of_chemical_formulas
*_List_of_biomolecules
*_List_of_inorganic_compounds
*_Periodic_table

values:
/wiki/Coordination_chemistry
mw-redirect
Coordination chemistry

values:
nofollow
external text
https://d-nb.info/gnd/4125872-1

values:
nofollow
external text
https://viaf.org/viaf/186605590

values: Category:CS1 French-language sources (fr)

values: Category:CS1 German-language sources (de)

values: Category:CS1 uses Russian-language script (ru)

values: Category:CS1 Russian-language sources (ru)

values: Category:Wikipedia indefinitely semi-protected pages

values: Category:Articles containing potentially dated statements from 2016

values: Category:All articles containing potentially dated statements

values: Category:Wikipedia articles with BNE identifiers

values: Category:Wikipedia articles with BNF identifiers

values: Category:Wikipedia articles with GND identifiers

values: Category:Wikipedia articles with LCCN identifiers

values: Category:Wikipedia articles with VIAF identifiers

values: Discussion about edits from this IP address [ctrl-alt-n]

values: A list of edits made from this IP address [ctrl-alt-y]

values: You are encouraged to create an account and log in; however, it is not mandatory

values: You're encouraged to log in; however, it's not mandatory. [ctrl-alt-o]

values:
/wiki/Periodic_table
View the content page [ctrl-alt-c]
c

values: Discussion about the content page [ctrl-alt-t]

values: p-namespaces navigation vectorTabs p-namespaces-label

values:
p-variants
navigation
vectorMenu emptyPortlet
p-variants-label

values:
This page is protected.
You can view its source [ctrl-alt-e]

values: Past revisions of this page [ctrl-alt-h]

values: p-views navigation vectorTabs p-views-label

values:
p-cactions
navigation
vectorMenu emptyPortlet
p-cactions-label

values:
mw-wiki-logo
/wiki/Main_Page
Visit the main page

values:
/wiki/Main_Page
Visit the main page [ctrl-alt-z]
z

values: Featured content – the best of Wikipedia

values: Find background information on current events

values:
/wiki/Special:Random
Load a random article [ctrl-alt-x]
x

values: portal navigation p-navigation p-navigation-label

values: Guidance on how to use and edit Wikipedia

values: About the project, what you can do, where to find things

values: A list of recent changes in the wiki [ctrl-alt-r]

values: portal navigation p-interaction p-interaction-label

values: List of all English Wikipedia pages containing links to this page [ctrl-alt-j]

values: Recent changes in pages linked from this page [ctrl-alt-k]

values:
/wiki/Wikipedia:File_Upload_Wizard
Upload files [ctrl-alt-u]
u

values: A list of all special pages [ctrl-alt-q]

values: Permanent link to this revision of the page

values: Link to connected data repository item [ctrl-alt-g]

values: Printable version of this page [ctrl-alt-p]

values: portal navigation p-wikibase-otherprojects p-wikibase-otherprojects-label

values:
interlanguage-link interwiki-ace
display: none;

values:
interlanguage-link interwiki-af
display: none;

values:
interlanguage-link interwiki-als
display: none;

values: የንጥረ ነገሮች ሠንጠረዥ – Amharic

values:
interlanguage-link interwiki-am
display: none;

values: Аелементқәа рпериодикатә система – Abkhazian

values:
interlanguage-link interwiki-ab
display: none;

values: جدول دوري – Arabic

values:
interlanguage-link interwiki-ar
display: none;

values: Tabla periodica d'os elementos – Aragonese

values:
interlanguage-link interwiki-an
display: none;

values: Tabellu periodicu a elementiľoru – Aromanian

values:
interlanguage-link interwiki-roa-rup
display: none;

values: পৰ্যাবৃত্ত তালিকা – Assamese

values:
interlanguage-link interwiki-as
display: none;

values:
interlanguage-link interwiki-ast
display: none;

values:
interlanguage-link interwiki-gn
display: none;

values: Kimyəvi elementlərin dövri sistemi – Azerbaijani

values:
interlanguage-link interwiki-az
display: none;

values: شیمیایی المنتلر تابلوسو – South Azerbaijani

values:
interlanguage-link interwiki-azb
display: none;

values: পর্যায় সারণী – Bangla

values:
interlanguage-link interwiki-bn
display: none;

values:
interlanguage-link interwiki-zh-min-nan
display: none;

values: Химик элементтарҙың периодик системаһы – Bashkir

values:
interlanguage-link interwiki-ba
display: none;

values: Перыядычная сістэма элементаў – Belarusian

values:
interlanguage-link interwiki-be
display: none;

values: Пэрыядычная сыстэма хімічных элемэнтаў – Belarusian (Taraškievica orthography)

values:
interlanguage-link interwiki-be-x-old
display: none;

values: पीरियॉडिक टेबल – Bhojpuri

values:
interlanguage-link interwiki-bh
display: none;

values: Периодична система – Bulgarian

values:
interlanguage-link interwiki-bg
display: none;

values:
interlanguage-link interwiki-bar
display: none;

values: རྩ་རྫས་ཀྱི་དུས་འཁོར་རེའུ་མིག། – Tibetan

values:
interlanguage-link interwiki-bo
display: none;

values:
interlanguage-link interwiki-bs
display: none;

values:
interlanguage-link interwiki-br
display: none;

values: Үелхэ системэ – Russia Buriat

values:
interlanguage-link interwiki-bxr
display: none;

values:
interlanguage-link interwiki-ca
display: none;

values: Элементсен периодла системи – Chuvash

values:
interlanguage-link interwiki-cv
display: none;

values:
interlanguage-link interwiki-ceb
display: none;

values:
interlanguage-link interwiki-cs
display: none;

values: Chapotera cheNhangande Dzakadevana – Shona

values:
interlanguage-link interwiki-sn
display: none;

values:
interlanguage-link interwiki-cy
display: none;

values: interlanguage-link interwiki-da badge-Q17559452 badge-recommendedarticle

values:
interlanguage-link interwiki-de
display: none;

values: ޕީރިއަޑިކް ތާވަލު – Divehi

values:
interlanguage-link interwiki-dv
display: none;

values: Keemiliste elementide perioodilisussüsteem – Estonian

values:
interlanguage-link interwiki-et
display: none;

values: Περιοδικός πίνακας των χημικών στοιχείων – Greek

values:
interlanguage-link interwiki-el
display: none;

values: Tabla periódica de los elementos – Spanish

values:
interlanguage-link interwiki-es
display: none;

values:
interlanguage-link interwiki-eo
display: none;

values: Tabra periúdica e los elementus – Extremaduran

values:
interlanguage-link interwiki-ext
display: none;

values:
interlanguage-link interwiki-eu
display: none;

values: جدول تناوبی – Persian

values: interlanguage-link interwiki-fa badge-Q17437798 badge-goodarticle

values:
interlanguage-link interwiki-hif
display: none;

values:
interlanguage-link interwiki-fo
display: none;

values: Tableau périodique des éléments – French

values:
interlanguage-link interwiki-fr
display: none;

values: Periodyk systeem fan de eleminten – Western Frisian

values:
interlanguage-link interwiki-fy
display: none;

values:
interlanguage-link interwiki-fur
display: none;

values:
interlanguage-link interwiki-ga
display: none;

values:
interlanguage-link interwiki-gv
display: none;

values:
interlanguage-link interwiki-gd
display: none;

values: Táboa periódica dos elementos – Galician

values:
interlanguage-link interwiki-gl
display: none;

values:
interlanguage-link interwiki-gan
display: none;

values:
interlanguage-link interwiki-ki
display: none;

values: આવર્ત કોષ્ટક – Gujarati

values:
interlanguage-link interwiki-gu
display: none;

values:
interlanguage-link interwiki-hak
display: none;

values:
interlanguage-link interwiki-ko
display: none;

values: Պարբերական աղյուսակ – Armenian

values:
interlanguage-link interwiki-hy
display: none;

values: आवर्त सारणी – Hindi

values:
interlanguage-link interwiki-hi
display: none;

values:
interlanguage-link interwiki-hr
display: none;

values:
interlanguage-link interwiki-io
display: none;

values: Periodiko a lamisaan dagiti elemento – Iloko

values:
interlanguage-link interwiki-ilo
display: none;

values: পর্যায় সারণী – Bishnupriya

values:
interlanguage-link interwiki-bpy
display: none;

values: interlanguage-link interwiki-id badge-Q17437796 badge-featuredarticle

values: Tabella periodic del elementos – Interlingua

values:
interlanguage-link interwiki-ia
display: none;

values: Элементты периодон системæ – Ossetic

values:
interlanguage-link interwiki-os
display: none;

values:
interlanguage-link interwiki-is
display: none;

values: Tavola periodica degli elementi – Italian

values:
interlanguage-link interwiki-it
display: none;

values: הטבלה המחזורית – Hebrew

values:
interlanguage-link interwiki-he
display: none;

values: Dhaptar unsur miturut lambang – Javanese

values:
interlanguage-link interwiki-jv
display: none;

values: ಆವರ್ತ ಕೋಷ್ಟಕ – Kannada

values:
interlanguage-link interwiki-kn
display: none;

values:
interlanguage-link interwiki-pam
display: none;

values: ქიმიურ ელემენტთა პერიოდული სისტემა – Georgian

values:
interlanguage-link interwiki-ka
display: none;

values: Химиялық элементтердің периодтық жүйесі – Kazakh

values:
interlanguage-link interwiki-kk
display: none;

values:
interlanguage-link interwiki-sw
display: none;

values: Химия элементъяслӧн период система – Komi

values:
interlanguage-link interwiki-kv
display: none;

values: Tablo klasifikasyon peryodik eleman – Haitian Creole

values:
interlanguage-link interwiki-ht
display: none;

values:
interlanguage-link interwiki-ku
display: none;

values: Элементтер мезгилдик системасы – Kyrgyz

values:
interlanguage-link interwiki-ky
display: none;

values: Химиядин элементрин девирдин система – Lezghian

values:
interlanguage-link interwiki-lez
display: none;

values: ຕາລາງທາດ – Lao

values:
interlanguage-link interwiki-lo
display: none;

values: جدول پشت سریک کاری عناصر – Northern Luri

values:
interlanguage-link interwiki-lrc
display: none;

values:
interlanguage-link interwiki-la
display: none;

values: Ķīmisko elementu periodiskā tabula – Latvian

values:
interlanguage-link interwiki-lv
display: none;

values: Periodesystem vun den Elementer – Luxembourgish

values:
interlanguage-link interwiki-lb
display: none;

values:
interlanguage-link interwiki-lt
display: none;

values: Periodiek systeem vaan eleminte – Limburgish

values:
interlanguage-link interwiki-li
display: none;

values:
interlanguage-link interwiki-ln
display: none;

values:
interlanguage-link interwiki-jbo
display: none;

values:
interlanguage-link interwiki-lmo
display: none;

values: Kémiai elemek periódusos rendszere – Hungarian

values:
interlanguage-link interwiki-hu
display: none;

values: Периоден систем на елементите – Macedonian

values:
interlanguage-link interwiki-mk
display: none;

values:
interlanguage-link interwiki-mg
display: none;

values: ആവർത്തനപ്പട്ടിക – Malayalam

values:
interlanguage-link interwiki-ml
display: none;

values:
interlanguage-link interwiki-mt
display: none;

values:
interlanguage-link interwiki-mi
display: none;

values: आवर्त सारणी – Marathi

values:
interlanguage-link interwiki-mr
display: none;

values: ქიმიურ ელემენტეფიშ პერიოდული სისტემა – Mingrelian

values:
interlanguage-link interwiki-xmf
display: none;

values:
interlanguage-link interwiki-arz
display: none;

values:
interlanguage-link interwiki-ms
display: none;

values:
interlanguage-link interwiki-min
display: none;

values: Nguòng-só ciŭ-gĭ-biēu – Min Dong Chinese

values:
interlanguage-link interwiki-cdo
display: none;

values:
interlanguage-link interwiki-mwl
display: none;

values: Үелэх систем – Mongolian

values:
interlanguage-link interwiki-mn
display: none;

values: ဒြပ်စင်အလှည့်ကျဇယား – Burmese

values:
interlanguage-link interwiki-my
display: none;

values: Tlapēuhcāyōtl nemachiyōtīlpāntli – Nāhuatl

values:
interlanguage-link interwiki-nah
display: none;

values:
interlanguage-link interwiki-nl
display: none;

values: आवर्त सारणी – Nepali

values:
interlanguage-link interwiki-ne
display: none;

values: तत्त्वमां – Newari

values:
interlanguage-link interwiki-new
display: none;

values: interlanguage-link interwiki-ja badge-Q17437798 badge-goodarticle

values: interlanguage-link interwiki-frr badge-Q17437798 badge-goodarticle

values: interlanguage-link interwiki-no badge-Q17506997 badge-featuredlist

values:
interlanguage-link interwiki-nn
display: none;

values:
interlanguage-link interwiki-oc
display: none;

values: Химий тӱҥлык-влакын периодик радамлыкше – Eastern Mari

values:
interlanguage-link interwiki-mhr
display: none;

values: ପର୍ଯ୍ୟାୟ ସାରଣୀ – Odia

values:
interlanguage-link interwiki-or
display: none;

values: Kimyoviy elementlar davriy sistemasi – Uzbek

values:
interlanguage-link interwiki-uz
display: none;

values: ਮਿਆਦੀ ਪਹਾੜਾ – Punjabi

values:
interlanguage-link interwiki-pa
display: none;

values:
interlanguage-link interwiki-pnb
display: none;

values:
interlanguage-link interwiki-pap
display: none;

values: Piiriadik tiebl – Jamaican Creole English

values:
interlanguage-link interwiki-jam
display: none;

values: Периоддэз сьӧрті химия ӧтувторрезлӧн тэчас – Komi-Permyak

values:
interlanguage-link interwiki-koi
display: none;

values: តារាងខួបនៃធាតុគីមី – Khmer

values:
interlanguage-link interwiki-km
display: none;

values:
interlanguage-link interwiki-pcd
display: none;

values:
interlanguage-link interwiki-pms
display: none;

values:
interlanguage-link interwiki-tpi
display: none;

values:
interlanguage-link interwiki-nds
display: none;

values:
interlanguage-link interwiki-pl
display: none;

values: Περιοδικόν Πινάκιν – Pontic

values:
interlanguage-link interwiki-pnt
display: none;

values:
interlanguage-link interwiki-pt
display: none;

values: Tabelul periodic al elementelor – Romanian

values:
interlanguage-link interwiki-ro
display: none;

values:
interlanguage-link interwiki-qu
display: none;

values: Періодічна сістема елементів – Rusyn

values:
interlanguage-link interwiki-rue
display: none;

values: Периодическая система химических элементов – Russian

values: Периодтаах таабыл – Sakha

values:
interlanguage-link interwiki-sah
display: none;

values: Taula periòdica de is elementos – Sardinian

values:
interlanguage-link interwiki-sc
display: none;

values:
interlanguage-link interwiki-sco
display: none;

values:
interlanguage-link interwiki-stq
display: none;

values:
interlanguage-link interwiki-st
display: none;

values: Sistemi periodik i elementeve – Albanian

values:
interlanguage-link interwiki-sq
display: none;

values:
interlanguage-link interwiki-scn
display: none;

values: ආවර්තිතා වගුව – Sinhala

values:
interlanguage-link interwiki-si
display: none;

values:
interlanguage-link interwiki-simple
display: none;

values:
interlanguage-link interwiki-sk
display: none;

values:
interlanguage-link interwiki-sl
display: none;

values:
interlanguage-link interwiki-so
display: none;

values:
interlanguage-link interwiki-ckb
display: none;

values:
interlanguage-link interwiki-srn
display: none;

values: Периодни систем – Serbian

values: interlanguage-link interwiki-sr badge-Q17437796 badge-featuredarticle

values: Periodni sistem elemenata – Serbo-Croatian

values:
interlanguage-link interwiki-sh
display: none;

values:
interlanguage-link interwiki-su
display: none;

values: interlanguage-link interwiki-fi badge-Q17559452 badge-recommendedarticle

values:
interlanguage-link interwiki-sv
display: none;

values:
interlanguage-link interwiki-tl
display: none;

values: தனிம அட்டவணை – Tamil

values:
interlanguage-link interwiki-ta
display: none;

values:
interlanguage-link interwiki-roa-tara
display: none;

values: Менделеевның периодик таблицасы – Tatar

values:
interlanguage-link interwiki-tt
display: none;

values: ఆవర్తన పట్టిక – Telugu

values:
interlanguage-link interwiki-te
display: none;

values: ตารางธาตุ – Thai

values: interlanguage-link interwiki-th badge-Q17437798 badge-goodarticle

values: Ҷадвали даврии элементҳои кимёӣ – Tajik

values:
interlanguage-link interwiki-tg
display: none;

values:
interlanguage-link interwiki-tr
display: none;

values: Himiki elementleriň periodik ulgamy – Turkmen

values:
interlanguage-link interwiki-tk
display: none;

values: Періодична система хімічних елементів – Ukrainian

values:
interlanguage-link interwiki-uk
display: none;

values: دوری جدول – Urdu

values:
interlanguage-link interwiki-ur
display: none;

values: ئېلېمېنتلارنىڭ دەۋرىي جەەدۋىلى – Uyghur

values: Himižiden elementoiden periodine tablut – Veps

values: interlanguage-link interwiki-vi badge-Q17437796 badge-featuredarticle

values:
interlanguage-link interwiki-fiu-vro
display: none;

values:
interlanguage-link interwiki-wa
display: none;

values:
interlanguage-link interwiki-vls
display: none;

values: פעריאדישע טאבעלע – Yiddish

values:
interlanguage-link interwiki-yo
display: none;

values: Mendeliejėva kemėniu elementu lentalė – Samogitian

values:
interlanguage-link interwiki-zh
display: none;

values: All languages (initial selection from common choices by you and others)

values: mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-Periodic_table rootpage-Periodic_table skin-vector action-view