Write formulae and names of the various salts formed when magnesium hydroxide is treated with sulphurous acid.

Explanation

`Mg(OH)_(2)` is a diacidic base and `H_(2)SO_(3)` is a dibasic acid. Hence, there is possibility of three different salts.
` Mg(OH)_(2) + H_(2)SO_(3) to underset("magnesium hydroxy bisulphite") (Mg(OH) HSO_(3) + H_(2)O)`
`Mg(OH) HSO_(3) + H_(2)SO_(3) to underset("magnesium bisulphite"")(Mg(HSO_(3))_(2) + H_(2)O)`
`Mg(OH)_(2) + H_(2)SO_(3) to underset("mgnesium bisulphite ")(Mg(HSO_(3))_(2) + H_(2)O)`
`Mg(HSO_(3))_(2) + Mg(OH)_(2) to underset("mgnesium sulhite")(2MgSO_(3) + 2H_(2)O)`