State the Gay Lussac’s law of combining volumes, explain with an illustration.

Gay Lussac’s law of combining volumes:

This law states that when gases react, they do so in volumes which bear a simple ratio to one another, and to the volume of the product(s) formed if gaseous, provided the temperature and pressure remain constant.

The law explains experimental facts about how gaseous atoms combine.

Example:

For the reaction: N_2(g) + 3H_2(g)→ 2NH_3(g)

1 vol. 3 vols. 2 vols.

1 volume of nitrogen combines with 3 volumes of hydrogen to form 2 volumes of ammonia.

Thus, the ratio is 1:3:2.

This satisfies the Gay Lussac’s law of combining volumes.