Na: S: O = 2: 1: 4
=> 2 at Na + 1 at. S + 4 at. O
=> F.chimica = Na2SO4
C: H = 3: 1
C = 3/12 = 0,25
H = 1/1 = 1 : 0,25
=> F.chimica = CH4
27,27% C + 72,72% O
C = 27,27/12 = 2,27
O = 72,72/16 = 4,54 : 2,27
=> F.cimica = CO2