Question

The gaseous decomposition of $C{l}_2{O}_7$ (gas) takes place according to following reaction:

$C{l}_2{O}_7\to C{l}_2\left(g\right)+\frac{7}{2}{O}_2\left(g\right)$

The decomposition is carried out in a closed container. The pressure measured after 15 minute and after a very long time were found to be 375 mm of Hg and 900 mm of Hg respectively. The ratio of partial pressure of $C{l}_2$ gas after a very long time and after 15 minute is:

• A. 6
• B. 4
• C. 5
• D. 1

Answer 1

The correct option is B 4

The gaseous decomposition takes place as

$C{l}_2{O}_7\left(g\right)\to C{l}_2\left(g\right)+\frac{7}{2}{O}_2\left(g\right)$
$t=0,P_0$ 0 0
$t=15,P_0-P$ P 7/2 P
$t=\infty$, 0 $P_0$ $7/2P_0$
$t=\infty ,\frac{9}{2}{P}_0+\frac{7}{2}P=375$
P $=$ 50 mm of Hg
$\frac{P_{C{l}_2}att=\infty }{P_{C{l}_2}att=15}=\frac{P_0}{P}=\frac{200}{50}=4$