Question

why deliquescence is minimized in dry conditions and efflorescence is maximized in dry conditions ?

Answer 1

Deliquescence, the process by which a substance absorbs moisture from the atmosphere until it dissolves in the absorbed water and forms a solution.

Efflorescence, spontaneous loss of water by a hydrated salt, which occurs when the aqueous vapor pressure of the hydrate is greater than the partial pressure of the water vapour in the air.

It is clear from the generalized definition of both phenomenas that if moisture is decreased as in the cadcase of dry conditions the deliquescence decreases. And the efflorescence iincreases.
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