Answer : The correct option is, empirical formula.
Explanation:
Empirical formula : It is the simplest form of the chemical formula which depicts the whole number of atoms of each element present in the compound.
Molecular formula : it is the chemical formula which depicts the actual number of atoms of each element present in the compound.
The equation used to calculate the valency is :
[tex]n=\frac{\text{molecular mass}}{\text{empirical mass}}[/tex]
Hence, the correct option is, empirical formula.
