Q.State Gay-Lussac's law of combining volume.

Reacting gas volumes (and gaseous product volumes) are always in a small whole-number ratio, at constant T and P.

Gay-Lussac's law of combining volumes (1808) states: when gases react with one another, they do so in volumes which bear a simple whole number ratio to one another and to the volume of the products, if these are also gases, provided all volumes are measured under the same conditions of temperature and pressure.

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