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In chemistry, a reactivity series (or reactivity series of elements) is an empirical, calculated, and structurally analytical progression [1] of a series of metals, arranged by their "reactivity" from highest to lowest.
Due to the moderate dielectric constant of CXB (ε = 7.9 [2]), PMMA acquires charges that can be screened by the addition of salt (e.g. tetrabutyl ammonium bromide), leading to a very good approximation of colloidal hard sphere. [3]
Additionally, the reactivity of two series of ketones are in the orders Cl 3 CCOCH 3 > CH 3 COCH 3 > C 6 H 5 COCH 3 and cyclohexanone > cyclopentanone > cycloheptanone > cyclooctanone. [7] [8] These orders of reactivity are the same as those observed for reactions that are well established as proceeding through nucleophilic attack on a carbonyl ...
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 ...
The Curtin–Hammett principle is a principle in chemical kinetics proposed by David Yarrow Curtin and Louis Plack Hammett.It states that, for a reaction that has a pair of reactive intermediates or reactants that interconvert rapidly (as is usually the case for conformational isomers), each going irreversibly to a different product, the product ratio will depend both on the difference in ...
With the advent of more reactive catalysts, equilibrium RCM is observed quite often which may lead to a greater product distribution. The mechanism can be expanded to include the various competing equilibrium reactions as well as indicate where various side-products are formed along the reaction pathway, such as oligomers.
Bromine is intermediate in reactivity between chlorine and iodine, and is one of the most reactive elements. Bond energies to bromine tend to be lower than those to chlorine but higher than those to iodine, and bromine is a weaker oxidising agent than chlorine but a stronger one than iodine.
The alcohol (1) is first converted into a reactive carbonothioyl intermediate such as a thionoester or xanthate 2. Heating of AIBN results in its homolytic cleavage, generating two 2-cyanoprop-2-yl radicals 9 , which each abstract a hydrogen from tributylstannane 3 to generate tributylstannyl radicals 4 and inactive 10 .