For example, one carbon and two oxygens (carbon dioxide). The two formulae are related by a whole number ratio such that if the empirical formula is multiplied by the ratio, it will yield the molecular formula.
[header] How to find molecular formula [title] Know the relationship between molecular and empirical formulae. [step] The empirical formula provides a ratio of atoms within a molecule, for example, two oxygens for every carbon. The molecular formula tells you how many of each of those atoms is present in the molecule.