How would adding the catalyst nitrogen monoxide (NO) affect the reaction 2SO2(g) + O2(g) → 2SO3(g)?

• A. It would decrease the rate of the reaction.
• B. It would increase the rate at which equilibrium is reached without affecting the position of equilibrium.
• C. It would increase the yield of SO3 at equilibrium.
• D. It would shift the equilibrium position toward the formation of SO3.

Answer: (B)

Verified step by step guidance

1. Understand that a catalyst provides an alternative reaction pathway with a lower activation energy, which increases the rate at which the reaction reaches equilibrium.
2. Recognize that catalysts do not affect the thermodynamics of the reaction, meaning they do not change the equilibrium constant or the position of equilibrium.
3. Recall that the reaction given is: \(2SO_2(g) + O_2(g) \rightarrow 2SO_3(g)\), and adding nitrogen monoxide (NO) as a catalyst will speed up both the forward and reverse reactions equally.
4. Conclude that while the catalyst increases the rate at which equilibrium is established, it does not increase the yield of \(SO_3\) or shift the equilibrium position toward products or reactants.
5. Therefore, the correct understanding is that the catalyst increases the rate at which equilibrium is reached without affecting the equilibrium composition.