1. Assume a 100g Sample
* This makes the calculations easier. We now have 67.6 g of uranium (U) and 32.4 g of fluorine (F).
2. Convert Grams to Moles
* Divide the mass of each element by its molar mass:
* Uranium (U): 67.6 g / 238.03 g/mol = 0.284 mol
* Fluorine (F): 32.4 g / 19.00 g/mol = 1.71 mol
3. Find the Mole Ratio
* Divide each mole value by the smallest mole value:
* Uranium (U): 0.284 mol / 0.284 mol = 1
* Fluorine (F): 1.71 mol / 0.284 mol = 6.03 ≈ 6
4. Write the Empirical Formula
* The mole ratio tells us the simplest whole-number ratio of atoms in the compound.
* The empirical formula is UF₆ (uranium hexafluoride).
