K2O – CaO
K2O = Mr = K2O = 39 x 2 + 16 x 1 = 94
K2 = 39 x 2 / 94 x 100 = 83
O = 16 x 1 / 94 x 100 = 17
94 + 83 + 17 = 194
CaO = Mr = CaO = 40 x 1 + 16 x 1 = 56
Ca = 40 x 1 / 56 x 100 = 71
O = 16 x 1 / 56 x 100 = 28
56 + 71 + 28 = 155
CO2 – SO2
CO2 = Mr = CO2 = 12 x 1 + 16 x 2 = 44
C = 12 x 1 / 44 x 100 = 27
O2 = 16 x 2 / 44 x 100 = 72
44 + 27 + 72 = 143
SO2 = Mr = SO2 = 32 x 1 + 16 x 2 = 64
S = 32 x 1 / 64 x 100 = 50
O2 = 16 x 2 / 64 x 100 = 50
64 + 50 + 50 = 164