Determine the chemical formula of aluminium chloride. Show your working by identifying the metal ion and non-metal ion, and then the chemical formula.

Step 1: Identify the metal ion and non-metal ion

The metal ion in this compound is Aluminium (Al). In its ionic form, Aluminium typically has a charge of +3 because it loses three electrons to achieve a stable electron configuration. This is often written as Al3+.

The non-metal ion in this compound is Chloride (Cl). In its ionic form, Chloride typically has a charge of -1 because it gains one electron to achieve a stable electron configuration. This is often written as Cl-.

Step 2: Determine the chemical formula

To create a neutral compound, the charges of the ions must balance out. In this case, we need three Chloride ions (each with a charge of -1) to balance out the +3 charge of the Aluminium ion.

Therefore, the chemical formula of aluminium chloride is AlCl3.