What is the empirical formula of a compound composed of 3.25% hydrogen ( H ), 19.36% carbon ( C ), and 77.39% oxygen ( O ) by mass?

Answer 1

The empirical formula is H₂CO₃.

Detailed explanation:

Empirical formula is based off of proportions, making actual amounts trivial. Let's assume you have 100 grams of this molecule. Then you'd have 3.25 gram, 19.36 grams, 77.39 grams of H,C, and O respectively. Convert each into moles by dividing by their molar masses. You will get 3.22, 1.61, 4.84 for H,C,O respectively. You then divide each mole count by the lowest mole count of the three, so 1.61. This gives you the mole ratio between the three, in other words, the empirical formula, of 2, 1, 3.