The ratio between the volumes occupied by 22 grams of carbon dioxide and 10 grams of hydrogen gas is:

1:10

Reason — Molar mass of CO₂ = 12 + 2 x 16 = 44 g/mole

∴ Moles of 22g CO₂ = $\frac{22}{44}$ = 0.5

Molar mass of H₂ = 2 x 1 = 2 g/mole

∴ Moles of 10g H₂ = $\frac{10}{2}$ = 5

Under the same conditions of temperature and pressure, the volume of a gas is directly proportional to the number of moles. Therefore, the volume ratio will be the same as the mole ratio.

Volume ratio = $\frac{\text{Vol. of CO}_2}{\text{Vol. of H}_2}$ = $\frac{0.5}{5}$ = 1 : 10