Question

A gas cylinder of capacity of 20 dm3 is filled with gas X the mass of which is 10 g. When the same cylinder is filled with hydrogen gas at the same temperature and pressure the mass of the hydrogen is 2 g, hence the relative molecular mass of the gas is :
1. 5
2. 10
3. 15
4. 20

August 4, 2024

Answer

10

Working

Vapour density of gas = 10/2 = 5 g

Molecular weight = 2 × Vapour density

= 2 × 5 = 10 g

Hence, the relative molecular mass of gas is 10 g

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