Reactivity and development of the transition state

Abstraction of hydrogen by the highly reactive chlorine atom has a low act According to the postulate, then, the transition state is reached before the reaction has proceeded very far, and when the carbon-hydrogen bond is only slightly stretched. Atoms and electrons are still distributed much as they were in the reactants carbon is still nearly tetrahedral. The methyl group has developed little free-radical character. 

in the attack by a reagent of high reactivity, the transition state tends to resemble the reactant in the attack by a reagent of low reactivity, the transition state tends to resemble the products. 

Most of this should be familiar to the student from previous courses in chemistry. What we shall concentrate on here will be the application of these principles to organic analysis. 

The presence of carbon or hydrogen in a compound is detected by combustion heating with copper oxide, which converts carbon into carbon dioxide and hydrogen into water. Problem How could each of these products be identified ) 

Covalently bonded halogen, nitrogen, and sulfur must be converted into inorganic ions, which can then be detected in already familiar ways. This conversion is accomplished in either of two ways (a) through sodium fusion, treatment with hot molten sodium metal  

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F re 2.11. Potential energy changes during progress of reaction reactivity and development of the transition state. Difficult reaction transition state reached late, resembles products. Easy reaction transition state reached early, resembles reactants. 

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