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  2. Syn and anti addition - Wikipedia

    en.wikipedia.org/wiki/Syn_and_anti_addition

    The concepts of syn and anti addition are used to characterize the different reactions of organic chemistry by reflecting the stereochemistry of the products in a reaction. The type of addition that occurs depends on multiple different factors of a reaction, and is defined by the final orientation of the substituents on the parent molecule .

  3. Matrix (chemical analysis) - Wikipedia

    en.wikipedia.org/wiki/Matrix_(chemical_analysis)

    A(extract) is the peak area of analyte, when diluted with matrix extract. A(standard) is the peak area of analyte in the absence of matrix. The concentration of analyte in both standards should be the same. A matrix effect value close to 100 indicates absence of matrix influence.

  4. Antarafacial and suprafacial - Wikipedia

    en.wikipedia.org/wiki/Antarafacial_and_suprafacial

    An example is the [1,3]-hydride shift, in which the interacting frontier orbitals are the allyl free radical and the hydrogen 1s orbitals. The suprafacial shift is symmetry-forbidden because orbitals with opposite algebraic signs overlap. The symmetry allowed antarafacial shift would require a strained transition state and is also unlikely. In ...

  5. 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 ...

  6. Stereoselectivity - Wikipedia

    en.wikipedia.org/wiki/Stereoselectivity

    In chemistry, stereoselectivity [1] is the property of a chemical reaction in which a single reactant forms an unequal mixture of stereoisomers during a non-stereospecific creation of a new stereocenter or during a non-stereospecific transformation of a pre-existing one. [2]

  7. Category:Subfields of chemistry - Wikipedia

    en.wikipedia.org/.../Category:Subfields_of_chemistry

    Chemical biology (1 C, 16 P) C. Carbohydrate chemistry (5 C, 81 P) ... Pages in category "Subfields of chemistry" This category contains only the following page.

  8. Accessible surface area - Wikipedia

    en.wikipedia.org/wiki/Accessible_surface_area

    Note that the probe radius depicted here is of smaller scale than the typical 1.4Å. The accessible surface area (ASA) or solvent-accessible surface area (SASA) is the surface area of a biomolecule that is accessible to a solvent. Measurement of ASA is usually described in units of square angstroms (a standard unit of measurement in molecular ...

  9. Polar surface area - Wikipedia

    en.wikipedia.org/wiki/Polar_surface_area

    PSA is a commonly used medicinal chemistry metric for the optimization of a drug's ability to permeate cells. Molecules with a polar surface area of greater than 140 angstroms squared (Å 2 ) tend to be poor at permeating cell membranes. [ 1 ]