Q. $A + B = C + D$. If initially the concentration of $A\ \ and\ B$ are both equal but at equilibrium, concentration of $D$ will be twice of that of $A$, then what will be the equilibrium constant of reaction?

A) $\frac{4}{9}$
B) $\frac{9}{4}$
C) $\frac{1}{9}$
D) 4
Explanation

(d)
$A + B = C + D$
$x$ $x$ 0 0 At initial
$2x$ $2x$ At equilibrium
$K_{c} = \frac{\lbrack C\rbrack\lbrack D\rbrack}{\lbrack A\rbrack\lbrack B\rbrack} = \frac{2x \times 2x}{x \times x} = 4$

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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