Question

What is the empirical formula of a substance that contains 0.117 mol of carbon, 0.233 mol of hydrogen, and 0.117 mol of oxygen?

Answer 1

Empirical formula of a compound gives the proportions of the elements in that compound but it does not define the actual arrangement and number of atoms.

Let the empirical formula of compound be $C_{x}H_{y}O_{z}$.

The ratio of number of moles of C, H and O can be calculated as follows:

$C:H:O=0.117:0.233:0.117$

Simplifying the ratio,

$C:H:O=\frac{0.117}{0.117}:\frac{0.233}{0.117}:\frac{0.117}{0.117}=1:1.99:1=1:2:1$

Thus, the value of x, y and z will be 1, 2 and 1 respectively.

Therefore, the empirical formula will be  $CH_{2}O$.