Mr(HNO3) = 1 + 14 + 3 * 16 = 63
Mr(Ca(OH)2) = 40 + 2 * (16 + 1) = 74
Mr(FeO) = 56 + 16 = 72
Mr(S) = 32
Mr(KOH) = 39 + 16 + 1 = 56
Mr(P2O5) = 2 * 31 + 5 * 16 = 142
Mr(CaCO3) = 40 + 12 + 3 * 16 = 100
Mr(Mg) = 24
Mr(Na2SiO3) = 2 * 23 + 28 + 3 * 16 = 122
Mr(O2) = 2 * 16 = 32
Mr(HF) = 1 + 19 = 20
Mr(CuO) = 64 + 16 = 80