Question

For the reaction $A\left(g\right)+3B\left(g\right)\rightleftharpoons 2C\left(g\right)$ at ${27}^{o}C,$ 2 moles of A, 4 moles of B and 6 moles of C are present in 2 litre vessel. If $K_c$ for the reaction is 1.2, the reaction will proceed in:

• A. Forward direction
• B. Backward direction
• C. The reaction will always be in equilibrium
• D. none of these

Answer 1

The correct option is A Forward direction

Given reaction: $A\left(g\right)+3B\left(g\right)\rightleftharpoons 2C\left(g\right)$
$Q_C=\frac{{\left(\frac{n_C}{V}\right)}^2}{\left(\frac{n_A}{V}\right){\left(\frac{n_B}{V}\right)}^3}$
On putting values,
$Q_C=\frac{{\left(\frac{6}{2}\right)}^2}{\left(\frac{2}{2}\right){\left(\frac{4}{2}\right)}^3}=\frac{9}{8}=1.125$
As, $Q_C<K_C$ so reaction will proceed in forward direction.