Making a salt from an insoluble metal oxide

Copper sulfate is often made because of its colour, but making white salts is just as good, just more difficult for the students to visualise, as the solution is not coloured. Therefore making Zinc Chloride is a bit more of a challenge. 

To make a salt from an insoluble metal oxide and an acid, the metal oxide must be reacted with the acid to produce a salt and water. The reaction can be represented by the following equation:

Metal oxide + Acid → Salt + Water

For example, if the metal oxide is magnesium oxide (ZnO) and the acid is hydrochloric acid (HCl), the reaction would be:

ZnO + 2HCl → ZnCl2 + H2O

In this reaction, the salt produced is magnesium chloride (ZnCl2).