Question

How will you determine the empirical formulae?

Answer 1

Definition of the empirical formula:

1. A formula that gives the simplest ratio of the atoms of all the elements in the molecule.

Determination of the empirical formula:

1. Write the molecular formula of the compound.
2. Divide the number of atoms of all the elements with a specific number so as to obtain a simple ratio of the number of atoms.
3. Thus, the empirical formula is determined.

Example:

1. The molecular formula of Benzene is $\mathbf{\left(}{\mathbf{C}}_{\mathbf{6}}{\mathbf{H}}_{\mathbf{6}}\mathbf{\right)}$, showing there are six carbon atoms and six hydrogen atoms.
2. Thus, the ratio of the number of atoms of carbon and hydrogen is $6:6$
3. Dividing the numerator and denominator by $6$, we get the ratio as $1:1$.
4. Thus, the empirical formula has one carbon atom and one hydrogen atom. Thus, the empirical formula of benzene is $\mathbf{\left(}\mathbf{CH}\mathbf{\right)}$