Question

Which ion will correctly complete the formula _________2hpo4?

Answer 1

The charge of the ion, HPO₄⁻² is equal to -2. This is the same as the one written before it as it appears in the formula of the substance. Since, in the given chemical formula, HPO₄ does not have any multiplier, the charge of the atom or ion that should appear before it is +1. The atoms that will have a charge of +1 are those in group A1. These are Na+, Li+, K+, Rb+, Cs+ and Fr+.