Why is anhydrous copper sulfate a white powder, while #CuSO_4*5H_2O# a blue crystal?

1 Answer
Jul 31, 2017

Answer:

Because the waters of hydration are incorporated into the crystal structure of the solvate.

Explanation:

#"Copper sulfate pentahydrate"#, #CuSO_4*5H_2O#, gives beautiful macroscopic crystals.....

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The water molecules are actually incorporated into the coordination sphere of the copper ion. Dry the crystals thoroughly (no easy task), and you are left with anhydrous #CuSO_4#, a white salt.