MGCO3 + MGSO4

Arrange the following sulphates of alkaline earth metals in order of decreasing thermal stability : BaSO_4 , MgSO_4, CaSO_4,SrSO_4 .

Determine degree of hardness in term of ppm of CaCO_3 of 10^(-3) molar MgSO_4 (aq).

Al(NO_3) has higher coagulating power then MgSO_4 for Fe(OH)_3 sol.

Which out of MgSO_4 or BaSO_4 is more soluble in water?