Page 24 - Curriculum Visions Dynamic Book

Copper sulphate
One of the best known compounds of copper is copper sulphate (formerly known as blue vitriol because of its deep blue colour).
It is prepared by reacting copper oxide or copper carbonate with
warm, dilute sulphuric acid. The solution then turns a translucent blue.
To make copper sulphate crystals, the solution is evaporated until
it is saturated (it can hold no more copper sulphate in solution). Large crystals of copper sulphate can be grown in this solution by suspending a small “seed” crystal in the saturated solution, around which larger crystals will form. Smaller crystals are produced by evaporating the solution to a small volume. Each technique is shown in the pictures
on this page.
EQUATION: Producing copper sulphate
Copper oxide + dilute sulphuric acid ➪ copper sulphate + water
CuO(s) + H2SO4(aq) ➪ CuSO4(aq) + Hydrogen
Oxygen
H2O(l)
+
Copper
◆◆ + Sulphur ➡
 Dilute sulphuric acid is poured on to (black) copper oxide
 The reaction occurs as the reagents are stirred.
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