The cation which gives white precipitate of its hydroxide when treated With aqueous ammonium sulphide solution is :

${\mathrm{Al}}^{3+}$gives a white precipitate of its hydroxide when treated with aqueous ammonia sulphide solution. Ammonium hydroxide was added to a solution containing aluminium cations, and the result was a milky white precipitate. Even after adding excessive ammonia solution, the white precipitate does not dissolve. On heating, there is no reaction occurs.