"Reagent A reagent is a substance or compound added to a system to cause a chemical reaction, or added to test if a reaction occurs. The terms ""reactant"" and ""reagent"" are often used interchangeably—however, a reactant is more specifically a substance ""consumed"" in the course of a chemical reaction. ""Solvents"", though involved in the reaction, are usually not called reactants. Similarly, ""catalysts"" are not consumed by the reaction, so they are not reactants. In biochemistry, especially in connection with enzyme-catalyzed reactions, the reactants are commonly called substrates. In organic chemistry, the term ""reagent"" denotes a chemical ingredient (a compound or"
"is unequal, the transformation is referred to as a nuclear reaction or radioactive decay.) The type of chemical reactions a substance may undergo and the energy changes that may accompany it are constrained by certain basic rules, known as chemical laws. Energy and entropy considerations are invariably important in almost all chemical studies. Chemical substances are classified in terms of their structure, phase, as well as their chemical compositions. They can be analyzed using the tools of chemical analysis, e.g. spectroscopy and chromatography. Scientists engaged in chemical research are known as chemists. Most chemists specialize in one or more sub-disciplines."
"formation of the compound from its elements; such a reaction is called an endothermic reaction. In explosive technology only materials that are exothermic—that have a net liberation of heat and have a negative heat of formation—are of interest. Reaction heat is measured under conditions either of constant pressure or constant volume. It is this heat of reaction that may be properly expressed as the ""heat of explosion."" A chemical explosive is a compound or mixture which, upon the application of heat or shock, decomposes or rearranges with extreme rapidity, yielding much gas and heat. Many substances not ordinarily classed as"
"Name reaction A name reaction is a chemical reaction named after its discoverers or developers. Among the tens of thousands of organic reactions that are known, hundreds of such reactions are well-known enough to be named after people. Well-known examples include the Grignard reaction, the Sabatier reaction, the Wittig reaction, the Claisen condensation, the Friedel-Crafts acylation, and the Diels-Alder reaction. Books have been published devoted exclusively to name reactions; the Merck Index, a chemical encyclopedia, also includes an appendix on name reactions. As organic chemistry developed during the 20th century, chemists started associating synthetically useful reactions with the names of"
"Zeisel determination The Zeisel determination or Zeisel test is a chemical test for the presence of esters or ethers in a chemical substance. It is named after the Czech chemist Simon Zeisel (1854–1933). In a qualitative test a sample is first reacted with a mixture of acetic acid and hydrogen iodide in a test tube. The ensuing reaction results in the cleavage of the ether or the ester into an alkyl iodide and respectively an alcohol or an carboxylic acid. By heating this mixture, the gases are allowed to come into contact with a piece of paper higher up the"
"below by the example of glucose: Molisch's test Molisch's test is a sensitive chemical test, named after Austrian botanist Hans Molisch, for the presence of carbohydrates, based on the dehydration of the carbohydrate by sulfuric acid or hydrochloric acid to produce an aldehyde, which condenses with two molecules of a phenol (usually α-naphthol, though other phenols such as resorcinol and thymol) also give colored products), resulting in a red- or purple-coloured compound. The test solution is combined with a small amount of Molisch's reagent (α-naphthol dissolved in ethanol) in a test tube. After mixing, a small amount of concentrated sulfuric"
"specific reagent is the active ingredient of an in-house test. Analyte-specific reagent Analyte-specific reagents (ASRs) are a class of biological molecules which can be used to identify and measure the amount of an individual chemical substance in biological specimens. The U.S. Food and Drug Administration (FDA) defines ""analyte specific reagents"" (ASRs) in ""21 CFR 864.4020"" as “antibodies, both polyclonal and monoclonal, specific receptor proteins, ligands, nucleic acid sequences, and similar reagents which, through specific binding or chemical reaction with substances in a specimen, are intended to use in a diagnostic application for identification and quantification of an individual chemical substance"
"Schiff test The Schiff test is an early organic chemistry name reaction developed by Hugo Schiff, and is a relatively general chemical test for detection of many organic aldehydes that has also found use in the staining of biological tissues. The Schiff reagent is the reaction product of a dye formulation such as fuchsin and sodium bisulfite; pararosaniline (which lacks an aromatic methyl group) and new fuchsin (which is uniformly mono-methylated ""ortho"" to the dye's amine functionalities) are not dye alternatives with comparable detection chemistry. In its use as a qualitative test for aldehydes, the unknown sample is added to"
"Ames test The Ames test is a widely employed method that uses bacteria to test whether a given chemical can cause mutations in the DNA of the test organism. More formally, it is a biological assay to assess the mutagenic potential of chemical compounds. A positive test indicates that the chemical is mutagenic and therefore may act as a carcinogen, because cancer is often linked to mutation. The test serves as a quick and convenient assay to estimate the carcinogenic potential of a compound because standard carcinogen assays on mice and rats are time-consuming (taking two to three years to"
"Molisch's test Molisch's test is a sensitive chemical test, named after Austrian botanist Hans Molisch, for the presence of carbohydrates, based on the dehydration of the carbohydrate by sulfuric acid or hydrochloric acid to produce an aldehyde, which condenses with two molecules of a phenol (usually α-naphthol, though other phenols such as resorcinol and thymol) also give colored products), resulting in a red- or purple-coloured compound. The test solution is combined with a small amount of Molisch's reagent (α-naphthol dissolved in ethanol) in a test tube. After mixing, a small amount of concentrated sulfuric acid is slowly added down the"
"Research chemical Research chemicals are chemical substances used by scientists for medical and scientific research purposes. One characteristic of a research chemical is that it is for laboratory research use only; a research chemical is not intended for human or veterinary use. This distinction is required on the labels of research chemicals, and is what exempts them from regulation under parts 100-740 in Title 21 of the Code of Federal Regulations (21CFR). Research chemicals are fundamental in the development of novel pharmacotherapies. Common medical laboratory uses include ""in vivo"" and animal testing to determine therapeutic value, toxicology testing by contract"
"based on the chemical it reacts with, allowing one to know what chemical is in the solution. An example is Heller's test where a test tube containing proteins has strong acids added to it. A cloudy ring forms where the substances meet, indicating the acids are denaturing the proteins. The cloud is a sign that proteins are present in a liquid. The method is used to detect proteins in a person's urine. The flame test is a more well known version of the chemical test. It is only used on metallic ions. The metal powder is burned, causing an emission"
"the environment. It is used to test: It can also involve the elemental analysis of samples, e.g., water sources, for items like: Wet chemistry Wet chemistry is a form of analytical chemistry that uses classical methods such as observation to analyze materials. It is called wet chemistry since most analyzing is done in the liquid phase. Wet chemistry is also called bench chemistry since many tests are performed at lab benches. Wet chemistry commonly uses laboratory glassware such as beakers and graduated cylinders to prevent materials from being contaminated or interfered with by unintended sources. Gasoline, Bunsen burners, and crucibles"
"Chemical change Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. Some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. Understanding chemical changes is a major part of the science of chemistry. When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an energy change"
"Chemical trap In chemistry, a chemical trap is a chemical compound that is used to detect an unstable chemical compounds. The method relies on efficiency of bimolecular reactions with reagents to produce a more easily characterize trapped product. In some cases, the trapping agent is used in large excess. A famous example is the detection of cyclobutadiene released upon oxidation of cyclobutadieneiron tricarbonyl. When this degradation is conducted in the presence of an alkyne, the cyclobutadiene is trapped as a bicyclohexadiene. The requirement for this trapping experiment is that the oxidant (ceric ammonium nitrate) and the trapping agent be mutually"
"the discoverers or developers; in many cases, the name is merely a mnemonic. Some cases of reactions that were not really discovered by their namesakes are known. Examples include the Pummerer rearrangement, the Pinnick oxidation and the Birch reduction. Although systematic approaches for naming reactions based on the reaction mechanism or the overall transformation exist (such as the IUPAC Nomenclature for Transformations), the more descriptive names are often unwieldy or not specific enough, so people names are often more practical for efficient communication. Name reaction A name reaction is a chemical reaction named after its discoverers or developers. Among the"
"does not support this mechanism or the sulfonamides as the chromogenic product. Schiff test The Schiff test is an early organic chemistry name reaction developed by Hugo Schiff, and is a relatively general chemical test for detection of many organic aldehydes that has also found use in the staining of biological tissues. The Schiff reagent is the reaction product of a dye formulation such as fuchsin and sodium bisulfite; pararosaniline (which lacks an aromatic methyl group) and new fuchsin (which is uniformly mono-methylated ""ortho"" to the dye's amine functionalities) are not dye alternatives with comparable detection chemistry. In its use"
"Analyte-specific reagent Analyte-specific reagents (ASRs) are a class of biological molecules which can be used to identify and measure the amount of an individual chemical substance in biological specimens. The U.S. Food and Drug Administration (FDA) defines ""analyte specific reagents"" (ASRs) in ""21 CFR 864.4020"" as “antibodies, both polyclonal and monoclonal, specific receptor proteins, ligands, nucleic acid sequences, and similar reagents which, through specific binding or chemical reaction with substances in a specimen, are intended to use in a diagnostic application for identification and quantification of an individual chemical substance or ligand in biological specimens.” In simple terms an analyte"
"several characteristics of a chemical reaction such as whether the reaction is exergonic or endergonic. Additionally the properties of a product can make it easier to extract and purify following a chemical reaction, especially if the product has a different state of matter than the reactants. Reactants are molecular materials used to create chemical reactions. The atoms aren't created or destroyed. The materials are reactive and reactants are rearranging during a chemical reaction. Here is an example of reactants: CH + O. A non-example is CO + HO or ""energy"". Spontaneous reaction Catalysed reaction Much of chemistry research is focused"
"Drug reaction testing Drug reaction testing uses a genetic test to predict how a particular person will respond to various prescription and non-prescription medications. It checks for genes that code for specific liver enzymes which activate, deactivate, or are influenced by various drugs. There are currently four genetic markers commonly tested for: 2D6, 2C9, 2C19, and 1A2. This testing has been done for some time by drug companies working on new drugs, but is relatively newly available to the general public. Strattera is the first drug to mention the test in the official documentation, although it doesn't specifically recommend that"
"or smell), consistency, and crystal structure; a place where it was found or where the discoverer comes from; the name of a scientist; a mythological figure; an astronomical body; the shape of the molecule; and even fictional figures. All elements that have been isolated have trivial names. In scientific documents, international treaties, patents and legal definitions, names for chemicals are needed that identify them unambiguously. This need is satisfied by systematic names. One such system, established by the International Union of Pure and Applied Chemistry (IUPAC), was established in 1950. Other systems have been developed by the American Chemical Society,"
"guide its applications. Chemical property A chemical property is any of a material's properties that becomes evident during, or after, a chemical reaction; that is, any quality that can be established only by changing a substance's chemical identity. Simply speaking, chemical properties cannot be determined just by viewing or touching the substance; the substance's internal structure must be affected greatly for its chemical properties to be investigated. When a substance goes under a chemical reaction, the properties will change drastically, resulting in chemical change. However, a catalytic property would also be a chemical property. Chemical properties can be contrasted with"
"chemical matter in and on cells. These reagents included antibodies (polyclonal and monoclonal), oligomers, all sorts of model organisms and immortalised cell lines, reagents and methods for molecular cloning and DNA replication, and many others. Tool compounds are also important reagents in biology; they are small molecules or biochemicals like siRNA or antibodies that are known to affect a given biomolecule—for example a drug target—but are unlikely to be useful as drugs themselves, and are often starting points in the drug discovery process. Many natural products, such as curcumin, are hits in almost any assay in which they are tested,"
"mushrooms: Developed by Julius Schäffer to help with the identification of ""Agaricus"" species. A positive reaction of Schaeffer's test, which uses the reaction of aniline and nitric acid on the surface of the mushroom, is indicated by an orange to red color; it is characteristic of species in the section ""Flavescentes"". The compounds responsible for the reaction were named schaefferal A and B to honor Schäffer. Two intersecting lines are drawn on the surface of the cap, the first with aniline or aniline water, the second with an aqueous solution of 65% nitric acid. The test is considered positive when"
"classifying substances. For example, many rocks exist as mineral complexes composed of multiple ions that do not occur in fixed proportions or spatial relationships to one another. A related philosophical problem is whether chemistry is the study of substances or reactions. Atoms, even in a solid, are in perpetual motion and under the right conditions many chemicals react spontaneously to form new products. A variety of environmental variables contribute to a substance's properties, including temperature and pressure, proximity to other molecules and the presence of a magnetic field. As Schummer puts it, ""Substance philosophers define a chemical reaction by the"
"Reactivity (chemistry) In chemistry, reactivity is the impetus for which a chemical substance undergoes a chemical reaction, either by itself or with other materials, with an overall release of energy. ""Reactivity"" refers to: The chemical reactivity of a single substance (reactant) covers its behavior in which it: The chemical reactivity of a substance can refer to the variety of circumstances (conditions that include temperature, pressure, presence of catalysts) in which it reacts, in combination with the: The term ""reactivity"" is related to the concepts of ""chemical stability"" and ""chemical compatibility"". ""Reactivity"" is a somewhat vague concept in chemistry. It appears"
"reactions in organic chemistry are name reactions designated after their discoverers. In a substitution reaction, a functional group in a particular chemical compound is replaced by another group. These reactions can be distinguished by the type of substituting species into a nucleophilic, electrophilic or radical substitution. In the first type, a nucleophile, an atom or molecule with an excess of electrons and thus a negative charge or partial charge, replaces another atom or part of the ""substrate"" molecule. The electron pair from the nucleophile attacks the substrate forming a new bond, while the leaving group departs with an electron pair."
"in a mixture, where other components interfere with its detection. The trapping agent, for example a dye, reacts with the chemical to be detected, giving a product that is more easily detected. Chemical trap In chemistry, a chemical trap is a chemical compound that is used to detect an unstable chemical compounds. The method relies on efficiency of bimolecular reactions with reagents to produce a more easily characterize trapped product. In some cases, the trapping agent is used in large excess. A famous example is the detection of cyclobutadiene released upon oxidation of cyclobutadieneiron tricarbonyl. When this degradation is conducted"
"became a separate branch of analytical chemistry called instrumental analysis. Because of the high volume of wet chemistry that must be done in today's society and new quality control requirements, many wet chemistry methods have been automated and computerized for streamlined analysis. The manual performance of wet chemistry mostly occurs in schools. Qualitative methods use changes in information that cannot be quantified to detect a change. This can include a change in color, smell, texture, etc. Chemical tests use reagents to indicate the presence of a specific chemical in an unknown solution. The reagents cause a unique reaction to occur"
"the colors found in a flame test, are produced in a bead test, which is a qualitative test for determining metals. A platinum loop is moistened and dipped in a fine powder of the substance in question and borax. The loop with the adhered powders is then heated in a flame until it fuses and the color of the resulting bead observed. Color of chemicals The color of chemicals is a physical property of chemicals that in most cases comes from the excitation of electrons due to an absorption of energy performed by the chemical. What is seen by the"
"Color reaction In chemistry, a color reaction or colour reaction is a chemical reaction that is used to transform colorless chemical compounds into colored derivatives which can be detected visually or with the aid of a colorimeter. The concentration of a colorless solution cannot normally be determined with a colorimeter. The addition of a color reagent leads to a color reaction and the absorbance of the colored product can then be measured with a colorimeter. A change in absorbance in the ultraviolet range cannot be detected by eye but can be measured by a suitably equipped colorimeter. A special colorimeter"
"are consumed) are known as stoichiometric coefficients. One molecule of A combines with two of B to form 3 of C, so if we use the symbol [X] for the number of moles of chemical X, If the reaction takes place in a closed system at constant temperature and volume, without a build-up of reaction intermediates, the ""reaction rate"" is defined as where is the stoichiometric coefficient for chemical X. The reaction rate has some functional dependence on the concentrations of the reactants, and this dependence is known as the ""rate equation"" or ""rate law"". This law generally cannot be"
"Crossover experiment (chemistry) In chemistry, a crossover experiment is a method used to study the mechanism of a chemical reaction. In a crossover experiment, two similar but distinguishable reactants simultaneously undergo a reaction as part of the same reaction mixture. The products formed will either correspond directly to one of the two reactants (non-crossover products) or will include components of both reactants (crossover products). The aim of a crossover experiment is to determine whether or not a reaction process involves a stage where the components of each reactant have an opportunity to exchange with each other. The results of crossover"