What are the rules for writing a chemical formula? [3 MARKS]

Rules: 1 Mark each

The rules for writing a chemical formula are as follows:

• The valencies or charges on the ion must balance.
• When a compound consists of a metal and a non-metal, the name or symbol of the metal is written first. Whereas non-metals are written on the right.
• In compounds formed with polyatomic ions, the ion is enclosed in a bracket before writing the number to indicate the ratio.