Q. An element M forms the oxide M 2 O 3 . What will be the formula of its sulphate. Share with your friends Share 0 Rishabh Mittal answered this Dear Student, 7. bM2O3 , here O has valency 2 and M has valency 3.We know that suplhate has valency 2.So, Sulphate of M isM2SO43 . Regards -2 View Full Answer