Which of the following reaction(s) have = ? — Chemical Equilibrium Chemistry Question

💡 Solution & Explanation

Step 1 - Understand the Relation Between \(K_p\) and \(K_c\) The relationship between the two equilibrium constants for a gaseous reaction is: \[K_p = K_c(RT)^{\Delta n_g}\] where $\Delta n_g = \sum n_{\text{g, products}} - \sum n_{\text{g, reactants}}$ For $K_p = K_c$: $(RT)^{\Delta n_g} = 1 \implies \Delta n_g = 0$ Step 2 - Option (A): \ce{H2(g) + I2(g) <=> 2HI(g)} $\Delta n_g = 2 - (1 + 1) = 0 \implies K_p = K_c$ **Correct.** Step 3 - Option (B): \ce{N2(g) + O2(g) <=> 2NO(g)} $\Delta n_g = 2 - (1 + 1) = 0 \implies K_p = K_c$ **Correct.** Step 4 - Option (C): \ce{2NO(g) + Cl2(g) <=> 2NOCl(g)} $\Delta n_g = 2 - (2 + 1) = -1 \implies K_p = \dfrac{K_c}{RT} \neq K_c$ **Incorrect.** Step 5 - Option (D): \ce{2SO2(g) + O2(g) <=> 2SO3(g)} $\Delta n_g = 2 - (2 + 1) = -1 \implies K_p = \dfrac{K_c}{RT} \neq K_c$ **Incorrect.** Step 6 - Summary | Option | Reaction | $\Delta n_g$ | $K_p = K_c$? | |--------|----------|-------------|--------------| | A | \ce{H2 + I2 <=> 2HI} | 0 | Yes | | B | \ce{N2 + O2 <=> 2NO} | 0 | Yes | | C | \ce{2NO + Cl2 <=> 2NOCl} | -1 | No | | D | \ce{2SO2 + O2 <=> 2SO3} | -1 | No | \[\text{Correct Options: } \boxed{\text{A, B}}\]