Question

One mole of $N_2{O}_4$ at 300 K is kept in a closed container under 1 atm pressure. It is heated to 600 K when 20% by mass of $N_2{O}_4$ decomposes to ${}^{\prime }{NO}_2^{\prime }\left(g\right)$. The resultant pressure is:

• A. 1.2 atm
• B. 2.4 atm
• C. 2 atm
• D. 1 atm

Answer 1

Answer: (B)

2.4 atm

$20\%$ of $1=\frac{20}{100}\times 1=0.2$

$N_2{O}_4\rightleftharpoons 2N{O}_2$

$1$ $0$

$-0.2$ $0.2\times 2$

$\overline{0.80.4}$

at $300K$ ideal gas $e{q}^n$

$PV=nRT$

$1\times V=1.0\times R\times 300$.....(1)

at $600K=PV=nRT$

$P_1\times V=(0.8+0.4)\times R\times 600$.......(2)

Divide $e{q}^n$ by $1$

$P_1\frac{1.2\times 600}{1\times 300}$

$2.5atm$