In a 500 mL flask, the degree of dissociation of $PCl_{5}$ at equilibrium is 40% and the initial amount is 5 moles. The value of equilibrium constant in $mol\ L^{- 1}$ for the decomposition of $PCl_{5}$ is

Question

Dr. Abubacker · Accepted Answer

(b)
$PCl_{5}\ \ \ \ \ \  \rightleftharpoons \ \ \ \ \ \ \ PCl_{3}\ \ \  + \ \ \ \ Cl_{2}$ Initial moles
5 0 0
5(1- ) 5 5 Moles at equilibrium
$\frac{5(1 - \ )}{0.5}$ $\frac{5}{0.5}$ $\frac{5}{0.5}$ Conc. At equilibrium
40%
0.4
$K_{c}\ \ \ \ \ \ \frac{\left\lbrack PCl_{3} \right\rbrack\left\lbrack Cl_{2} \right\rbrack}{\left\lbrack PCl_{5} \right\rbrack}\$
$\frac{\frac{5\ \ \ \ \ \ \ \ \ 0.4}{0.5}\ \ \ \ \ \ \ \ \ \ \frac{5\ \ \ \ \ \ \ \ \ 0.4}{0.5}}{\frac{5\ \ \ \ \ \ \ \ \ 0.6}{0.5}}\ \ \ \ \ \ \frac{16}{6}$
2.66 mol/L

Q. In a 500 mL flask, the degree of dissociation of $PCl_{5}$ at equilibrium is 40% and the initial amount is 5 moles. The value of equilibrium constant in $mol\ L^{- 1}$ for the decomposition of $PCl_{5}$ is

Explanation

Reviewed by Dr. Abubacker

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