Noun
dihydrate (plural dihydrates)
(chemistry) A hydrate whose solid contains two molecules of water of crystallization per molecule, or per unit cell
Crystallization from aqueous solution gives the dihydrate RaCl 2 ·2H 2 O, isomorphous with its barium analog. Source: Internet
Like radium chloride, crystallization from aqueous solution gives the dihydrate RaBr 2 ·2H 2 O, isomorphous with its barium analog. Source: Internet
Upon addition of water, after a few tens of minutes plaster of Paris becomes regular gypsum (dihydrate) again, causing the material to harden or "set" in ways that are useful for casting and construction. Source: Internet