CBSE Class 11-science Answered

Let the total volume of the gaseous mixture be 100 L.

O₂ = 40 L, N₂ = 40 L, CO₂ = 10 L, CH₄ =10 L

From the above relation, we can calculate the mass of each gas present in the mixture in 22.4 L, 32 g O₂ is present ,

So, in 40 L, (32/22.4) x 40 g is present = 57.14 g.

Similarly,

Mass of N2 in the mixture = (28/22.4) x 40 = 50 g

Mass of CO2 in the mixture = (44/22.4) x 10 = 19.6 g

Mass of CH4 in the mixture = (16/22.4) x 10 = 7.14 g

Total mass of the gaseous mixture = 57.14 + 19.6 + 7.14 = 133.88 g

100 L of the gaseous mixture has a mass of (133.88/100) x 22.4 = 29.98 g  ≈    30 g

This means that 30 g is the molar mass of the gaseous mixture

Now, vapour density = molar mass / 2 = 30 / 2 =15