Q. 5 moles of $X$ are mixed with 3 moles of $Y$. At equilibrium for the reaction, $X + Y \rightleftharpoons Z,$ 2 moles of $Z$ are formed. The equilibrium constant for the reaction will be
A) $\frac{2}{3}$
B) $\frac{1}{2}$
C) $\frac{3}{2}$
D) $\frac{1}{4}$
Explanation
(a)
$X\ \ \ + \ \ \ \ \ Y \rightleftharpoons \ \ \ Z$
Initial conc., 5 3 0
At equilibrium $(5 - 2)(3 - 2)\ \ \ 2$
Equilibrium constant $\left( K_{c} \right) = \frac{\lbrack Z\rbrack}{\lbrack X\rbrack\lbrack Y\rbrack}$
$= \frac{2}{3 \times 1} = \frac{2}{3}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.