Atomic hydrogen combines with almost all elements but molecular h… - Vidyadip

Question

Atomic hydrogen combines with almost all elements but molecular hydrogen does not. Explain.

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Answer

Atomic hydrogen is very reactive whereas molecular hydrogen are quite stable. The chemical behaviour of dihydrogen (and for that matter any molecule) is determined, to a large extent, by bond dissociation enthalphy. The H - H bond dissociation enthalphy is the hoghest for a single bond between two atoms of any element. As a result, molecular hydrogen reacts only with a few elements.

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