1. Assume a 100 g Sample

* This makes the calculations easier. We have 29.6 g of oxygen and 70.4 g of fluorine.

2. Convert Grams to Moles

* Divide the mass of each element by its molar mass:

* Oxygen: 29.6 g / 16.00 g/mol = 1.85 mol

* Fluorine: 70.4 g / 19.00 g/mol = 3.71 mol

3. Find the Mole Ratio

* Divide each number of moles by the smallest number of moles (1.85 mol in this case):

* Oxygen: 1.85 mol / 1.85 mol = 1

* Fluorine: 3.71 mol / 1.85 mol = 2

4. Write the Empirical Formula

* The mole ratio tells us the simplest whole number ratio of atoms in the compound. The empirical formula is OF₂.