Assume there are 100g of the compound. Mass of carbon:20.01g Mass of oxygen:79.99g Number of mole of carbon:20.01/12=1.6675mol Number of mole of oxygen:79.99/32=2.4996875mol Mole ratio between carbon and oxygen: 1.6675/1.6675:2.4996875/1.6675 =1:1.499062969 1x2:1.499062969x2 =2:2.998125937 ≈2:3 Hence, the empirical formula: C2O3
