Reactivity, Equilibrium and Electronegativity
نویسنده
چکیده
The entha lpy AH of general d isplacement react ions A B + C D A D + C B is der ived w i t h the a id of the ion ic app rox ima t i on to chemica l bond ing . T h i s entha lpy compares favourab ly w e l l w i t h Pau l ing 's cor responding equat ion AH—— 46 (%B— ̂ d ) (%A — XC)These expressions are used as a basis to discuss var ious aspects of chemical r eac t i v i t y : reversals i n react iv i ty , ambident react iv i ty , the Hammet t re la t ion, the McDan ie l -Y i ngs t equat ion, the Drago E —C equat ion , the resolut ion of ac id st rength, the p ro ton af f in i t ies of negat ive and neu t ra l species and the ha rd and soft acid-base ( H S A B ) ru le . Qua l i ta t i ve ly , and i n some cases even quant i ta t ive ly , reasonable results are obta ined, demons t ra t ing the great f l e x i b i l i t y of an electronegat iv i ty-based theory of chemical react iv i ty .
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