Mr(MgSO4) = 24 + 32 + 16*4 = 120
Mr(ZnCl2) = 65 + 35,5*2 = 136
Mr(NaOH) = 23 + 16 + 1 = 40
Mr(Al2O3) = 27*2 + 16*3 = 102
Mr(MgSO4) = 24 + 32 + 16*4 = 120
Mr(ZnCl2) = 65 + 35,5*2 = 136
Mr(NaOH) = 23 + 16 + 1 = 40
Mr(Al2O3) = 27*2 + 16*3 = 102