Analysis of a compound shows that it contains 7.0 g nitrogen and 16.0 g oxygen. What is its empirical formula?
The empirical formula is the simplest whole number that defines constituent atoms in a species.
Using the given masses, and the atomic masses of each constituent, we define an empirical formula this way:
And thus we have the molar quantities of nitrogen, and oxygen respectively. To access the empirical formula, we simply divide thru by the LOWEST molar quantity, that of nitrogen:
And thus the empirical formula is
Note that to find the molecular formula we need an estimate of molecular mass.