Question

$A+B\leftrightharpoons C+D$, $K_c$ for this reaction is $10$. If $1,2,3,4$ mole/litre of $A,B,C$ and $D$ respectively are present in a container at ${25}^{o}C$, the direction of reaction will be:

• A. from left to right
• B. from right to left
• C. reaction is at equilibrium
• D. unpredictable

Answer 1

The correct option is A from left to right

$A+B\rightleftharpoons C+D$

$1$ $2$ $3$ $4$

$K_C=10$

$Q_c=\frac{\left[D\right]\left[C\right]}{\left[A\right]\left[B\right]}=\frac{4\times 3}{2\times 1}=\frac{6}{1}$

$Q_c<K_C$ so products favoured left to right (in the forward direction).

Hence, option A is correct.