Question

What is efflorescence? Give an example.

Answer 1

efflorescence is the migration of a salt to the surface of a porous material, where it forms a coating.The essential process comprises the dissolving of an internally-held salt in water, or occasionally in another solvent. The water, with the salt now held in solution, migrates to the surface, then evaporates, leaving a coating of the salt.
example.
sodium carbonate deca hydrate

Answer 2

Efflorescence is a crystaline deposit on surfaces of masonry, stucco or concrete. It is whitish in appearance, and is sometimes referred to as "whiskers".