`Mg_3N_2` when reats with water, gives off `NH_3` but HCl is not evolved when `MgCl_2` reacts with water at room temperature. Give reasons.

Explanation

`Mg_3N_2` is a salt of the strong base, `Mg(OH)_2` and the weak acid, `NH_3`. Hence it gets hudrolysed to give `NH_3`.
`Mg_3N_2 + 6H_2O to 3Mg(OH)_2 + 2NH_3 uarr`
`MgCl_2`, on the other hand, is a salt of the strong base, `Mg(OH)_2` and the strong acid, `HCl. Hence it does not undergo hydrolysis.