Page 25 - Curriculum Visions Dynamic Book

 The solution soon clears and becomes bright blue. This is copper sulphate dissolved in water.
anhydrous: a substance from which water has been removed by heating. Many hydrated salts are crystalline. When they are heated and the water is driven off, the material changes
to an anhydrous powder.
hydrate: a solid compound in crystalline form that contains molecular water. Hydrates commonly form when a solution of a soluble salt is evaporated. The water that forms part of a hydrate crystal is known as the “water of crystallization”. It can usually be removed by heating, leaving an anhydrous salt.
reagent: a starting material for a reaction.
 Copper sulphate crystals like these of varying size can be grown from a saturated copper sulphate solution.
 Crystals of hydrated copper sulphate (above)
are deep blue. However, when the water is driven
off, the substance changes to a very light blue powder, called anhydrous copper sulphate (right).
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