Q.
For a reaction equilibrium, $N_{2}O_{4}(g) \rightleftharpoons 2NO_{2}(g)$, the concentrations of $N_{2}O_{4}\ and\ NO_{2}$ at equilibrium are $4.8 \times 10^{- 2}\ and\ 1.2 \times 10^{- 2}$ mol/L respectively. The value of $K_{c}$ for the reaction is
A) $3 \times 10^{- 3}$ mol/L
B) $3.3 \times 10^{- 3}$ mol/L
C) $3 \times 10^{- 1}$ mol/L
D) $3.3 \times 10^{- 1}$ mol/L
Explanation
(a)
According to law of mass action
$K_{c} = \frac{\left\lbrack NO_{2} \right\rbrack^{2}}{\lbrack N_{2}O_{4}\rbrack} = \frac{\left\lbrack 1.2 \times 10^{- 2} \right\rbrack^{2}}{4.8 \times 10^{- 2}} = 0.3 \times 10^{- 2} = 3 \times 10^{- 3}$ mol/L
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.