Question

Gaseous mixture of contains $56g$ of $N_2,$ $44g$ of ${CO}_2$ and $16g$ of ${CH}_4.$ The total pressure of mixture is $720atm$ of $Hg$ The partial pressure of ${CH}_4$ is:

• A. $75atm$
• B. $160atm$
• C. $180atm$
• D. $215atm$

Answer 1

Answer: (A)

$75atm$

According to Dalton's Law of Partial pressure,

Partial pressure of $C{H}_4=\left(X_{C{H}_4}\right)\cdot P_{total}$

$X_{C{H}_4}=\frac{no.ofmolesofC{H}_4}{Totalno.ofmoles}=\frac{\frac{16}{16}}{\frac{16}{16}+\frac{44}{44}+\frac{56}{14}}=\frac{1}{6}$

$⟹P_{C{H}_4}=\left(\frac{1}{6}\right)\left(720\right)$ $atm$

$⟹P_{C{H}_4}=120$ $atm$