Molecular Formula: MgSO4nH2O( n= 0, 1, 2, 3, 4, 5, 6, 7) Molecular Weight: 120.37+ 18n ( n= 0, 1, 2, 3, 4, 5, 6, 7) CAS No: 10034-99-8 ( MgSO47H2O) 7487-88-9 ( MgSO4 ) ....