1. Calculate the empirical formula mass:
* C: 3 atoms * 12.01 g/mol = 36.03 g/mol
* H: 5 atoms * 1.01 g/mol = 5.05 g/mol
* O: 1 atom * 16.00 g/mol = 16.00 g/mol
* Total empirical formula mass = 36.03 + 5.05 + 16.00 = 57.08 g/mol
2. Determine the ratio between the molar mass and the empirical formula mass:
* Molar mass of the compound / Empirical formula mass = (Given Molar Mass) / 57.08 g/mol
3. Multiply the subscripts in the empirical formula by the ratio from step 2:
* This will give you the molecular formula.
Example:
Let's say the molar mass of the compound is 114.16 g/mol.
* Ratio = 114.16 g/mol / 57.08 g/mol = 2
* Molecular formula = (C3H5O) * 2 = C6H10O2
Therefore, you need to provide the molar mass of the unknown compound to determine its molecular formula.
