Mr(MgSO₄)=24+32+16x4=120
Mr(Na₂SiO₃)=23x2+28+16x3=122
Mr[Fe(NO₃)₃=56+(14+16x3)x3=242
Mr(K₃PO₄)=23x3 +31+16x4=164
Mr(BaSO₄)=137+32+16x4=233
Mr(Li₂SiO₃)=7x2 +28+16x3=90
Mr[Zn₃(PO₄)₂]=65x3+(31+16x4)x2=385
Mr[Ba(NO₃)₂=137+(14+48)x3=323
Mr[Cu(NO₂)₂]=64+(14+16x2)x2=156