Question

For the reaction $A+B\rightleftharpoons 2C$, $2$ moles of $A$ reacts with $3$ moles of $B$. If the equilibrium constant $K_c$ is $4$ at ${400}^{o}C$, what will be the moles of $C$ at equilibrium?

• A. $1.8$
• B. $2.4$
• C. $3.0$
• D. $1$

Answer 1

The correct option is B $2.4$

$\begin{array}{c}{K}_c=\frac{(2x{)}^2}{(2-x)(3-x)}=4\\ x^2=6+x^2-5x\\ x=1.2\end{array}$

$\begin{array}{c}\text{Concentration of}C\\ \text{at equilibrium}=2x\\ =2\times 1.2\\ =2.4\end{array}$