Question

For a reaction $A_{\left(g\right)}\rightleftharpoons B_{\left(g\right)}$, if initial pressure at ${300}^{o}C$ is 1 atm and its $K_p$ is 4,. Then calculate $P_B$ at equilibrium state.

• A. $\frac{1}{5}atm$
• B. $\frac{2}{5}atm$
• C. $\frac{4}{5}atm$
• D. $\frac{3}{5}atm$

Answer 1

The correct option is C $\frac{4}{5}atm$

Given:

$T={300}^{0}C$

$P_A=1atm$

$K_p=4$

For the reaction $A\left(g\right)\leftrightarrow B\left(g\right)$

$K_p=\frac{\left[P_B\right]}{\left[P_A\right]}$

So, $\left[P_B\right]=4X1=4atm$

Thus total pressure =$4+1=5atm$

$P_B=1atmX4/5=4/5atm$

Option C is correct answer