Define efflorescence. Give examples. - Vidyadip

Question

Define efflorescence. Give examples.

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Answer

Crystalline hydrated salts which on exposure to the atmosphere lose their water of crystallisation partly or completely and change into a powder. This phenomenon is called efflorescent and the salts are called efflorescent.
Examples: $CuSO_4.5H_2O, MgSO_4.7H_2O, Na_2CO_3.10H_2O$

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