Question

A gas mixture contains $24\%$ nitrogen, $32\%$ oxygen and remaining is hydrogen by volumes at a given temperature and pressure then what is the mole fraction of hydrogen?

(assume there is no reaction between the gases)

• A. $0.44$
• B. $0.24$
• C. $0.91$
• D. $0.56$

Answer 1

Answer: (C)

$0.91$

Volume of Nitrogen $=24$ g Molar mass of $N_2$ $=28$ g

Volume of Oxygen $=32$ g Molar mass of $O_2$ $=32$ g

Volume of Hydrogen $=44$ g Molar mass of $H_2$ $=2$ g

Mole number=$\frac{Givenmass}{Molarmass}$

Mole number $N_2=24/28=0.9$

Mole number $O_2=32/32=1$

Mole number $H_2=44/2=22$

Total moles $=0.9+1+22=23.9=24$

Mole fraction of $H_2=\frac{No.ofmolesofhydrogen}{Totalmoles}$

$=22/24=0.91$