Liebig test is used to estimate :

For the estimate of "Carbon and hydrogen," Liebig's technique is employed.

Principle: Pure oxygen is present while a known mass of an organic molecule is cooked. The water and carbon dioxide that are produced are gathered and weighed.

The masses of carbon dioxide and water are used to compute the proportions of carbon and hydrogen in the chemical. Based on their conversion to CO and ${\mathrm{H}}_2\mathrm{O}$, respectively, carbon and hydrogen content of an organic molecule may be estimated.