define water of crystallization...?

Answer 1

Water of crystallization is water that occurs in crystals but is not covalently bonded to a host molecule or ion. Upon crystallization from water or moist solvents, many compounds incorporate water molecules in their crystalline frameworks. Often, in fact, the species of interest cannot be crystallized in the absence of water, even though no strong bonds to the "guest" water molecules may be apparent.

Classically, "water of crystallization" refers to water that is found in a crystalline framework of a metal complex but that is not directly bonded to the metal ion.

Answer 2

Water of crystallization are the non-bonded water molecules that are incorporated in certain compounds when they form crystals. For example, crystals of copper sulphate contain water of crystallization.
This water than generally be easily removed by heating of compound.