Water of Crystallization - Nomenclature

Nomenclature

In molecular formulas water of crystallization can be denoted in different ways:

• "hydrous compound⋅nH₂O" or "hydrous compound×nH₂O"

This notation is used when the compound only contains lattice water or when the crystal structure is undetermined. For example Calcium chloride: CaCl₂·2H₂O

• "hydrous compound(H₂O)_n"

A hydrate with coordinated water. For example Zinc chloride: ZnCl₂(H₂O)₄

• Both notations can be combined as for example in copper(II) sulfate: SO₄·H₂O