Q. A reaction is, $A + B \rightarrow C + D$. Initially we start with equal concentrations of $A$and $B$. At equilibrium, we find the moles of $C$ are two times of $A$. What is the equilibrium constant of the reaction?

A) 2
B) 4
C) $\frac{1}{2}$
D) $\frac{1}{4}$
Explanation

(b)
$A + B \rightleftharpoons C + D$
$a\ \ \ \ \ a\ \ \ \ \ \ 2a\ \ \ 2a$ at equilibrium
$\therefore\ \ K_{c} = \frac{\lbrack C\rbrack\lbrack D\rbrack}{\lbrack A\rbrack\lbrack B\rbrack}$
$= \frac{2a \times 2a}{a \times a} = 4$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.

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