Write the chemical formulae of the following.

(a) Magnesium chloride

(b) Calcium oxide

(c) Copper nitrate

(d) Aluminum chloride

(e) Calcium carbonate

Chemical formulae:

(a) Magnesium chloride = MgCl₂

For magnesium(Mg), the valency = 2

For chlorine (Cl), the valency = 1

Now criss-cross the symbol with the valency of another element. Thus, the chemical formula will be MgCl₂.

(b) Calcium oxide = CaO

(c) Copper nitrate = Cu(NO₃)₂

(d) Aluminum chloride = AlCl₃

(e) Calcium carbonate = CaCO₃