Question

$K_C=9$ for the reaction, $A+B\rightleftharpoons C+D$. If $A$ and $B$ are taken in equal amounts. Then what is the amount of $C$ in equilibrium?

• A. 0.75
• B. 0.98
• C. 1.23
• D. 2.45

Answer 1

Answer: (A)

0.75

$A+B\rightleftharpoons C+D$,
$a$ $a$ $0$ $0$
$a-ax$ $a-ax$ $ax$ $ax$

$K_C=\frac{ax\times ax}{(a-ax)\times (a-ax)}=(\frac{x}{1-x}{)}^2$

$9=(\frac{x}{1-x}{)}^2$

$\frac{x}{1-x}=|3|$

$x=0.75$