Chemistry 2002 JAMB Past Questions - Question 18: When a salt loses its water of crystallization to the atmosphere on exposure, the process is said to be

Correct Answer

A

Explanation

The process in which a salt loses its water of crystallization to the atmosphere on exposure is known as efflorescence. Efflorescence occurs when a hydrated salt, which contains water molecules in its crystal structure, loses those water molecules when exposed to air. This often results in the formation of a powdery white deposit on the surface of the salt crystals.

The phenomenon of efflorescence is common in certain salts, such as sulfate and carbonate salts, and is influenced by factors like humidity and temperature. When the salt crystals absorb moisture from the air, they dissolve in the water, and as the water evaporates, the salt re-crystallizes on the surface, leaving behind the characteristic white powder.