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  2. Radical clock - Wikipedia

    en.wikipedia.org/wiki/Radical_clock

    [3] [4] The Arrhenius equation can then be applied to calculate the rate constant for a specific temperature at which the radical clock reactions are conducted. When using a radical clock to study a reaction, there is an implicit assumption that the rearrangement rate of the radical clock is the same as when the rate of that rearrangement ...

  3. Radical (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Radical_(chemistry)

    In chemistry, a radical, also known as a free radical, is an atom, molecule, or ion that has at least one unpaired valence electron. [1] [2] With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spontaneously dimerize. Most organic radicals have short lifetimes.

  4. Reaction rate constant - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate_constant

    where A and B are reactants C is a product a, b, and c are stoichiometric coefficients,. the reaction rate is often found to have the form: = [] [] Here ⁠ ⁠ is the reaction rate constant that depends on temperature, and [A] and [B] are the molar concentrations of substances A and B in moles per unit volume of solution, assuming the reaction is taking place throughout the volume of the ...

  5. nth root - Wikipedia

    en.wikipedia.org/wiki/Nth_root

    The positive integer n is called the index or degree, and the number x of which the root is taken is the radicand. A root of degree 2 is called a square root and a root of degree 3, a cube root. Roots of higher degree are referred by using ordinal numbers, as in fourth root, twentieth root, etc. The computation of an n th root is a root extraction.

  6. Taft equation - Wikipedia

    en.wikipedia.org/wiki/Taft_equation

    The Taft equation is a linear free energy relationship (LFER) used in physical organic chemistry in the study of reaction mechanisms and in the development of quantitative structure–activity relationships for organic compounds. It was developed by Robert W. Taft in 1952 [2] [3] [4] as a modification to the Hammett equation. [5]

  7. Hydroxyl radical - Wikipedia

    en.wikipedia.org/wiki/Hydroxyl_radical

    In order to study gas phase interstellar chemistry, it is convenient to distinguish two types of interstellar clouds: diffuse clouds, with T=30-100 K, and n=10–1000 cm −3, and dense clouds with T=10-30K and density n= 10 4-10 3 cm −3. Ion chemical routes in both dense and diffuse clouds have been established for some works (Hartquist 1990).

  8. Benson group increment theory - Wikipedia

    en.wikipedia.org/wiki/Benson_group_increment_theory

    Once this is determined, all one needs to do is take the total value of Δ f H, subtract the Δ f H caused by the C−(C) 2 (H) 2 group(s), and then divide that number by two (due to two C−(C)(H) 3 groups), obtaining the value of the C−(C)(H) 3 group. From the knowledge of these two groups, Benson moved forward obtain and list functional ...

  9. Mass spectral interpretation - Wikipedia

    en.wikipedia.org/wiki/Mass_spectral_interpretation

    The base formula for the molecule is + and the degree of unsaturation is = (+) A negative value of u indicates the presence of heteroatoms in the molecule and a half-integer value of u indicates the presence of an odd number of nitrogen atoms. On addition of heteroatoms, the molecular formula is adjusted by the equivalent mass of carbon and ...