For the reaction A(g) 2B(g), the backward reaction rate constant is higher than the forward reaction rate constant by a factor of…

Question

For the reaction A(g) 2B(g), the backward reaction rate constant is higher than the forward reaction rate constant by a factor of 2500, at 1000 K. [Given: R = 0.0831 L atm mol^-1 K^-1] KP for the reaction at 1000 K is:

1. A. 83.1
2. B. 2.077×10^5
3. C. 0.033 (Correct answer)
4. D. 0.021

Correct Answer

Option C — 0.033

Detailed Solution & Explanation

The correct answer is 0.033.

Key Points

• $K_C=\dfrac{k_f}{k_b}=\dfrac{1}{2500}$ (backward is 2500 times faster).
• $K_P=K_C(RT)^{\Delta n_g}$ with $\Delta n_g=2-1=1$.
• $K_P=\dfrac{1}{2500}\times0.0831\times1000=0.033$.