Question

[TQB.VIII(3)]
State the Gay Lussac’s law of combining volumes, explain with an illustration.

Answer 1

Whenever gases react together, the volumes of the reacting gases and the products bear a simple whole number ratio, provided all the volumes are measured under similar conditions of temperature and pressure.
Steps:

1. Hydrogen combines with oxygen to form water
2. $H_2+\frac{1}{2}{O}_2\to H_{2}O$ (Skeletal equation)
3. $2H_{2\left(g\right)}+O_{2\left(g\right)}\to 2H_2{O}_{\left(g\right)}$ (balanced equation) (2 Volumes) + (1 volume) (2 Volumes) 2:1:2

Two volumes of hydrogen react with one volume of oxygen to form two volumes of water vapour that is the ratio by volume, which gases bears is 2:1:2, which is a simple whole-number ratio.