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  2. List of chemical classifications - Wikipedia

    en.wikipedia.org/wiki/List_of_chemical...

    Chemical classification systems attempt to classify elements or compounds according to certain chemical functional or structural properties. Whereas the structural properties are largely intrinsic, functional properties and the derived classifications depend to a certain degree on the type of chemical interaction partners on which the function is exerted.

  3. Covalent organic framework - Wikipedia

    en.wikipedia.org/wiki/Covalent_organic_framework

    MOFs are a class of porous polymeric material, consisting of metal ions linked together by organic bridging ligands and are a new development on the interface between molecular coordination chemistry and materials science. [8] COFs are another class of porous polymeric materials, consisting of porous, crystalline, covalent bonds that usually ...

  4. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...

  5. Functionality (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Functionality_(Chemistry)

    In organic chemistry, functionality is often used as a synonym for functional group. For example, a hydroxyl group can also be called a HO-function. [1] [2] Functionalisation means the introduction of functional groups, for example the functionalisation of a surface [3] (e.g. silanization for the specific modification of the adhesion of a surface)

  6. Retardation factor - Wikipedia

    en.wikipedia.org/wiki/Retardation_factor

    In chromatography, the retardation factor (R) is the fraction of an analyte in the mobile phase of a chromatographic system. [1] In planar chromatography in particular, the retardation factor R F is defined as the ratio of the distance traveled by the center of a spot to the distance traveled by the solvent front. [2]

  7. List of purification methods in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_purification...

    Recrystallization: In analytical and synthetic chemistry work, purchased reagents of doubtful purity may be recrystallised, e.g. dissolved in a very pure solvent, and then crystallized, and the crystals recovered, in order to improve and/or verify their purity.

  8. Isolobal principle - Wikipedia

    en.wikipedia.org/wiki/Isolobal_principle

    Figure 1: Basic example of the isolobal analogy. For his work on the isolobal analogy, Hoffmann was awarded the Nobel Prize in Chemistry in 1981, which he shared with Kenichi Fukui. [3] In his Nobel Prize lecture, Hoffmann stressed that the isolobal analogy is a useful, yet simple, model and thus is bound to fail in certain instances. [1]

  9. Reactivity–selectivity principle - Wikipedia

    en.wikipedia.org/wiki/Reactivity–selectivity...

    The sulfur radical was found to be more reactive (6*10 8 vs. 1*10 7 M −1.s −1) and less selective (selectivity ratio 76 vs 1200) than the carbon radical. In this case, the effect can be explained by extending the Bell–Evans–Polanyi principle with a factor δ {\displaystyle \delta \,} accounting for transfer of charge from the reactants ...