10L of a gas at `0^(@)C` and 760 mm pressure weighs 13.39g. Under identical conditions of temperature and pressure, ass of 10 L of hydrogen is 0.8928g. What is the molecular mass of the gas?

Explanation

Vapour density
`=("at "0^(@)C" and 1 atm pressure mass of 10L of a gas")/(" at "0^(@)" and 1 atm pressure mass of 10L "H_(2)" gas")`
`=(13.39)/(0.8928)=15`
`therefore`Molecular mass of the gas=2`xx`vapour density
`=2xx15=30`