What is the act of becoming, or state of being, a hydrate. Water of hydration (Chem.), water chemically combined with some substance to form a hydrate; -- distinguished from water of crystallization called?

hydration — The act of becoming, or state of being, a hydrate. Water of hydration (Chem.), water chemically combined with some substance to form a hydrate; -- distinguished from water of crystallization. (Webster's 1913.)

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