Question

The equilibrium constant $K_c$ for the reaction
$P_4\left(g\right)\rightleftharpoons 2P_2\left(g\right)$
is $1.4$ at ${400}^{\circ }C.$ Suppose that $3$ mole of $P_4\left(g\right)$ and $2$ moles of $P_2\left(g\right)$ are mixed in 2 litre container at ${400}^{\circ }C$. What is the value of reaction quotient $\left(Q_c\right)$?

• A. $\frac{3}{2}$
• B. $\frac{2}{3}$
• C. $1$
• D. None of these

Answer 1

The correct option is B $\frac{2}{3}$

$Q_c=\frac{[P_{2\left(g\right)}{]}^2}{\left[P_{4\left(g\right)}\right]}=\frac{{\left(\frac{2}{2}\right)}^2}{\frac{3}{2}}=\frac{2}{3}$