Question

For the reaction: $CO\left(g\right)+\frac{1}{2}{O}_2\left(g\right)\rightleftharpoons C{O}_2\left(g\right),K_p/K_c$ is

• A. $RT$
• B. $(RT{)}^{-1}$
• C. $(RT{)}^{-1/2}$
• D. $(RT{)}^{1/2}$

Answer 1

The correct option is C $(RT{)}^{-1/2}$

The relationship between $K_p{K}_p$ and $K_c{K}_c$ is $K_p=K_c\left(RT\right)$

$\Delta n{K}_p=K_c\left(RT\right)\Delta n$

For the equilibrium reaction $CO\left(g\right)+12O_2\left(g\right)\rightleftharpoons C{O}_2\left(g\right),Kp/Kc$

$\Delta n=1-(1+0.5)$

$=-0.5\Delta n$

$=1-(1+0.5)$

$=-0.5$

Hence,

$K_p=K_c\left(RT\right)\Delta n$

$=Kc\left(RT\right)-1/2$

$=\left(RT\right)-1/2K_p$