"was observed in a spectrum taken near the edge of the Sun. With a wavelength of about 588 nm, slightly less than the so-called ""D"" lines of sodium. the line could not be explained as due to any material known at the time, and so it was suggested by Lockyer, after he had observed it from London, that the yellow line was caused by an unknown solar element. He named this element helium after the Greek word 'Helios' meaning 'sun'. An observation of the new yellow line had been made earlier by Janssen at the 18 August 1868 solar eclipse,"
"of 46.612 days. Most of the remaining radioisotopes have half-lives that are less than a day. and are the most often studied NMR-active nuclei, having spins of and respectively. Hg is the modern chemical symbol for mercury. It comes from ""hydrargyrum"", a Latinized form of the Greek word ὑδράργυρος (""hydrargyros""), which is a compound word meaning ""water-silver"" (from ὑδρ- ""hydr-"", the root of ὕδωρ, ""water,"" and ἄργυρος ""argyros"" ""silver"") – since it is liquid like water and shiny like silver. The element was named after the Roman god Mercury, known for his speed and mobility. It is associated with the"
"body before being found on the earth. Lockyer and the English chemist Edward Frankland named the element with the Greek word for the Sun, ἥλιος (""helios""). At the great Indian eclipse of 1868 that occurred in Guntur, Janssen also demonstrated the gaseous nature of the red prominences, and devised a method of observing them under ordinary daylight conditions. One main purpose of his spectroscopic inquiries was to answer the question whether the Sun contains oxygen or not. An indispensable preliminary was the virtual elimination of oxygen-absorption in the Earth's atmosphere, and his bold project of establishing an observatory on the"
"the mineral fluorospar, which was used as a flux in metal working. Chlorine's name comes from the Greek word ""chloros"", meaning ""greenish-yellow"". Bromine's name comes from the Greek word ""bromos"", meaning ""stench"". Iodine's name comes from the Greek word ""iodes"", meaning ""violet"". Astatine's name comes from the Greek word ""astatos"", meaning ""unstable"". Tennessine is named after the US state of Tennessee. The halogens show trends in chemical bond energy moving from top to bottom of the periodic table column with fluorine deviating slightly. (It follows trend in having the highest bond energy in compounds with other atoms, but it has"
"spectrum of the sun (it is not known why the suffix ""-ium"", which is used for metals, was chosen). The other noble gases are neon (""new""), argon (""slow, lazy""), krypton (""hidden""), xenon (""stranger""), and radon (""from radium""). Many more elements have been given names that have little or nothing to do with their properties. Elements have been named for celestial bodies (helium, selenium, tellurium, for the sun, moon, and earth; cerium and palladium for Ceres and Pallas, two asteroids). They have been named for mythological figures, including Titans in general (titanium) and Prometheus in particular (promethium); Roman and Greek gods"
"is due to the very high nuclear binding energy (per nucleon) of helium-4 with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. Most helium in the universe is helium-4, the vast majority of which was formed during the Big Bang. Large amounts of new helium are being created by nuclear fusion of hydrogen in stars. Helium is named for the Greek Titan of the Sun, Helios. It was first detected as an unknown yellow spectral line signature in sunlight during a"
"Selenium Selenium is a chemical element with symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. Selenium (from Ancient Greek (selḗnē) ""Moon"") was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in , where it"
"for example, hydrogen (""water-producing""), oxygen (""acid-producing""), nitrogen (""soda-producing""), bromine (""stink""), and argon (""no reaction"") were based on Greek roots, while the names of iodine and chlorine were derived from the Greek words for their characteristic colors. Indium, rubidium, and thallium were similarly named for the colors of particular lines in their emission spectra. Iridium, which forms compounds of many different colors, takes its name from ""iris"", the Latin for ""rainbow"". The noble gases have all been named for their origin or properties. Helium comes from the Greek ""helios"", meaning ""sun"" because it was first detected as a line in the"
"""Phosphorus"" in Ancient Greece was the name for the planet Venus and is derived from the Greek words (φῶς = light, φέρω = carry), which roughly translates as light-bringer or light carrier. (In Greek mythology and tradition, Augerinus (Αυγερινός = morning star, still in use today), Hesperus or Hesperinus (΄Εσπερος or Εσπερινός or Αποσπερίτης = evening star, still in use today) and Eosphorus (Εωσφόρος = dawnbearer, not in use for the planet after Christianity) are close homologues, and also associated with Phosphorus-the-planet). According to the Oxford English Dictionary, the correct spelling of the element is phosphorus. The word phosphorous is"
"when the sun's light was less intense. The eclipse allowed Janssen to observe a spectral line never seen before, which was not associated with any known element. The same spectral line was confirmed by the English astronomer Norman Lockyer, who thinking the element only existed in the sun, named it helium, after the Greek Sun God. However, it wasn’t long before another British scientist had discovered helium on Earth. By dissolving the radioactive ore cleveite in acid, William Ramsay was able to collect a gas trapped within the rock, which had an atomic weight of 4, and the same spectral"
"the Greek word ""khalkόs"" (χαλκός) principally meaning copper (the term was also used for bronze/brass, any metal in the poetic sense, ore or coin), and the Latinised Greek word ""genēs"", meaning ""born"" or ""produced"". Sulfur has been known since antiquity, and oxygen was recognized as an element in the 18th century. Selenium, tellurium and polonium were discovered in the 19th century, and livermorium in 2000. All of the chalcogens have six valence electrons, leaving them two electrons short of a full outer shell. Their most common oxidation states are −2, +2, +4, and +6. They have relatively low atomic radii,"
"""water-silver"" (hydr- = water, argyros = silver) — since it is liquid like water and shiny like silver. The element was named after the Roman god Mercury, known for speed and mobility. It is associated with the planet Mercury; the astrological symbol for the planet is also one of the alchemical symbols for the metal. Mercury is the only metal for which the alchemical planetary name became the common name. The heaviest known group 12 element, copernicium, was first created on February 9, 1996, at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany, by Sigurd Hofmann, Victor Ninov et al."
"the identification of its atomic number 89. The name actinium originates from the Ancient Greek ""aktis, aktinos"" (ακτίς, ακτίνος), meaning beam or ray. Its symbol Ac is also used in abbreviations of other compounds that have nothing to do with actinium, such as acetyl, acetate and sometimes acetaldehyde. Actinium is a soft, silvery-white, radioactive, metallic element. Its estimated shear modulus is similar to that of lead. Owing to its strong radioactivity, actinium glows in the dark with a pale blue light, which originates from the surrounding air ionized by the emitted energetic particles. Actinium has similar chemical properties to lanthanum"
"with alpha particles. In 1811, the German chemist Johann Schweigger proposed that the name ""halogen"" – meaning ""salt producer"", from αλς [als] ""salt"" and γενειν [genein] ""to beget"" – replace the name ""chlorine"", which had been proposed by the English chemist Humphry Davy. Davy's name for the element prevailed. However, in 1826, the Swedish chemist Baron Jöns Jacob Berzelius proposed the term ""halogen"" for the elements fluorine, chlorine, and iodine, which produce a sea-salt-like substance when they form a compound with an alkaline metal. Fluorine's name comes from the Latin word ""fluere"", meaning ""to flow"", because it was derived from"
"taken from Greek mythology, meaning ""light-bearer"" (Latin ""Lucifer""), referring to the ""Morning Star"", the planet Venus. The term ""phosphorescence"", meaning glow after illumination, derives from this property of phosphorus, although the word has since been used for a different physical process that produces a glow. The glow of phosphorus is caused by oxidation of the white (but not red) phosphorus — a process now called chemiluminescence. Together with nitrogen, arsenic, antimony, and bismuth, phosphorus is classified as a pnictogen. Phosphorus is essential for life. Phosphates (compounds containing the phosphate ion, PO) are a component of DNA, RNA, ATP, and phospholipids."
"factories, coal-burning power plants, and metal sewers. The main source of elevated thallium concentrations in water is the leaching of thallium from ore processing operations. Thallium Thallium is a chemical element with symbol Tl and atomic number 81. It is a gray post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. Chemists William Crookes and Claude-Auguste Lamy discovered thallium independently in 1861, in residues of sulfuric acid production. Both used the newly developed method of flame spectroscopy, in which thallium produces a notable green spectral line. Thallium, from Greek"
"by Jöns Jakob Berzelius in his system of atomic symbols, and is an abbreviation of the element's New Latin name ""natrium"", which refers to the Egyptian ""natron"", a natural mineral salt mainly consisting of hydrated sodium carbonate. Natron historically had several important industrial and household uses, later eclipsed by other sodium compounds. Sodium imparts an intense yellow color to flames. As early as 1860, Kirchhoff and Bunsen noted the high sensitivity of a sodium flame test, and stated in Annalen der Physik und Chemie: In a corner of our 60 m room farthest away from the apparatus, we exploded 3"
"Palladium Palladium is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). These have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium"
"can regarded as a portmanteau of ""borax"" and ""carbon"". Aluminium was named by Humphry Davy in the early 1800s. It is derived from the Greek word ""alumen"", meaning bitter salt, or the Latin ""alum"", the mineral. Gallium is derived from the Latin ""Gallia"", referring to France, the place of its discovery. Indium comes from the Latin word ""indicum"", meaning indigo dye, and refers to the element's prominent indigo spectroscopic line. Thallium, like indium, is named after the Greek word for the color of its spectroscopic line: ""thallos"", meaning a green twig or shoot. ""Nihonium"" is named after Japan (""Nihon"" in"
"Actinism Actinism () is the property of solar radiation that leads to the production of photochemical and photobiological effects. ""Actinism"" is derived from the Greek ακτίς, ακτῖνος (a ray or beam). The word ""actinism"" is found, for example, in the terminology of imaging technology (esp. photography), medicine (concerning sunburn), and chemistry (concerning containers that protect from photo-degradation), and the concept of actinism is applied, for example, in chemical photography and X-ray imaging. Actinic () chemicals include silver salts used in photography and other light sensitive chemicals. In chemical terms, actinism is the property of radiation that lets it be absorbed"
"similar odor was known from tellurium compounds. Hence, Berzelius's first letter to Alexander Marcet stated that this was a tellurium compound. However, the lack of tellurium compounds in the Falun mine minerals eventually led Berzelius to reanalyze the red precipitate, and in 1818 he wrote a second letter to Marcet describing a newly found element similar to sulfur and tellurium. Because of its similarity to tellurium, named for the Earth, Berzelius named the new element after the Moon. In 1873, Willoughby Smith found that the electrical resistance of grey selenium was dependent on the ambient light. This led to its"
"metre, but as viewed through Earth's atmosphere, this is lowered to about 1.44 Gcd/m. However, the luminance is not constant across the disk of the Sun (limb darkening). The Sun is composed primarily of the chemical elements hydrogen and helium. At this time in the Sun's life, they account for 74.9% and 23.8% of the mass of the Sun in the photosphere, respectively. All heavier elements, called ""metals"" in astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%) being the most abundant. The Sun's original"
"to be eka-antimony, but was soon convinced that it was instead eka-silicon. Before Winkler published his results on the new element, he decided that he would name his element ""neptunium"", since the recent discovery of planet Neptune in 1846 had similarly been preceded by mathematical predictions of its existence. However, the name ""neptunium"" had already been given to another proposed chemical element (though not the element that today bears the name neptunium, which was discovered in 1940). So instead, Winkler named the new element ""germanium"" (from the Latin word, ""Germania"", for Germany) in honor of his homeland. Argyrodite proved empirically"
"Mercury (element) Mercury is a chemical element with symbol Hg and atomic number 80. It is commonly known as quicksilver and was formerly named hydrargyrum ( ). A heavy, silvery d-block element, mercury is the only metallic element that is liquid at standard conditions for temperature and pressure; the only other element that is liquid under these conditions is bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature. Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide). The red pigment vermilion is obtained by grinding natural cinnabar or synthetic mercuric sulfide. Mercury"
"in the Solar atmosphere. In this way it was proved that the chemical elements found in the Sun and stars were also found on Earth. Among those who extended the study of solar and stellar spectra was Norman Lockyer, who in 1868 detected bright, as well as dark, lines in solar spectra. Working with the chemist, Edward Frankland, to investigate the spectra of elements at various temperatures and pressures, he could not associate a yellow line in the solar spectrum with any known elements. He thus claimed the line represented a new element, which was called helium, after the Greek"
"the D because it was near the known D and D Fraunhofer line lines of sodium. He concluded that it was caused by an element in the Sun unknown on Earth. Lockyer and English chemist Edward Frankland named the element with the Greek word for the Sun, ἥλιος (""helios""). In 1881, Italian physicist Luigi Palmieri detected helium on Earth for the first time through its D spectral line, when he analyzed a material that had been sublimated during a recent eruption of Mount Vesuvius. On March 26, 1895, Scottish chemist Sir William Ramsay isolated helium on Earth by treating the"
"was associated with metals and metal-bearing rock in general; copper, and its alloy bronze, was one of the first metals to be used by humans. Oxygen's name comes from the Greek words ""oxy genes"", meaning ""acid-forming"". Sulfur's name comes from either the Latin word ""sulfurium"" or the Sanskrit word ""sulvere""; both of those terms are ancient words for sulfur. Selenium is named after the Greek goddess of the moon, Selene, to match the previously-discovered element tellurium, whose name comes from the Latin word ""telus"", meaning earth. Polonium is named after Marie Curie's country of birth, Poland. Livermorium is named for"
"heretofore unknown spectroscopic lines from the Sun; these could not be explained by any of the known elements in the 1870s. Many elements are named after the minerals in which they are found, e.g. calcium after Latin ""calx"" (lime), silicon is named after Latin ""silex"" (sand), sodium after soda and potassium after potash. In 1979, IUPAC published recommendations for their systematic element names to be used for yet unnamed or undiscovered elements as a placeholder, until the discovery of the element is confirmed and a permanent name is decided on. The recommendations are mostly ignored among scientists, who simply call"
"derives it from ""ithmid""; other possibilities include ""athimar"", the Arabic name of the metalloid, and a hypothetical ""as-stimmi"", derived from or parallel to the Greek. The standard chemical symbol for antimony (Sb) is credited to Jöns Jakob Berzelius, who derived the abbreviation from ""stibium"". The ancient words for antimony mostly have, as their chief meaning, kohl, the sulfide of antimony. The Egyptians called antimony ""mśdmt""; in hieroglyphs, the vowels are uncertain, but the Coptic form of the word is ⲥⲧⲏⲙ (stēm). The Greek word, στίμμι ""stimmi"", is probably a loan word from Arabic or from Egyptian ""stm"" O34:D46-G17-F21:D4 and is"
"""selenium"", after the moon. Silicon: In 1823, Berzelius prepared amorphous silicon by reducing potassium fluorosilicate with molten potassium metal. Bromine: Balard and Gmelin both discovered bromine in the autumn of 1825 and published their results in the following year. Helium: In 1868, Janssen and Lockyer independently observed a yellow line in the solar spectrum that did not match that of any other element. In 1895, in each case at around the same time, Ramsay, Cleve, and Langlet independently observed helium trapped in cleveite. Fluorine: André-Marie Ampère predicted an element analogous to chlorine obtainable from hydrofluoric acid, and between 1812 and"
"Manganese Manganese is a chemical element with symbol Mn and atomic number 25. It is not found as a free element in nature; it is often found in minerals in combination with iron. Manganese is a metal with important industrial metal alloy uses, particularly in stainless steels. Historically, manganese is named for pyrolusite and other black minerals from the region of Magnesia in Greece, which also gave its name to magnesium and the iron ore magnetite. By the mid-18th century, Swedish-German chemist Carl Wilhelm Scheele had used pyrolusite to produce chlorine. Scheele and others were aware that pyrolusite (now known"
"Bromine Bromine is a chemical element with symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly coloured gas. Its properties are thus intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825) and Antoine Jérôme Balard (in 1826), its name was derived from the Ancient Greek βρῶμος (""stench""), referencing its sharp and disagreeable smell. Elemental bromine is very reactive and thus does not occur free in nature, but in colourless soluble crystalline mineral halide salts,"
"in 1810, who named it chlorine, from the Greek word χλωρος (chlōros), meaning ""green-yellow."" Chlorine is a component of various compounds, including table salt. It is the second most abundant halogen and 21st most abundant chemical element in Earth's crust. The great oxidizing potential of chlorine led it to its bleaching and disinfectant uses, as well as uses of an essential reagent in the chemical industry. As a common disinfectant, chlorine compounds are used in swimming pools to keep them clean and sanitary. In the upper atmosphere, chlorine-containing molecules such as chlorofluorocarbons have been implicated in ozone depletion. ""Argon"" (symbol"