In a hydrocarbon solution, the gold compound (CH₃)₃AuPH₃ decomposes into ethane (C₂H₆) and a different gold compound, (CH₃)AuPH₃. The following mechanism has been proposed for the decomposition of (CH₃)₃AuPH₃:

Step 1: (CH₃)₃AuPH₃ k1 k -1 (CH₃)₃Au + PH₃ (fast)

Step 2: (CH₃)₃Au k2 C₂H₆ + (CH₃)Au (slow)

Step 3: (CH₃)Au + PH₃ ¡k3 1(CH₃)AuPH₃ (fast)

(f) What would be the effect on the reaction rate of adding PH₃ to the solution of (CH₃)₃AuPH₃?

Video transcript

Hi everyone for this problem. It reads hydrogen peroxide decomposes quickly into water and oxygen gas in the presence of a platinum catalyst. The decomposition reaction takes place in two steps. Will the rate of the reaction change if oxygen is removed from the reaction mixture? So we want to answer the question of Will the rate of the reaction change? Okay, so the given reaction is a two step reaction with one slow step and one fast step. The rate of reaction depends only on the rate of the slow reaction. This is why the slow step is known as the rate limiting step. Okay, so this is our rate limiting. So the first step of the reaction is a slow step and the second one is the fast step. Oxygen is a component or product of the fast step. Okay, as we can see here, any change we make to the fast step will not affect the overall rate of the reaction. Therefore changing the concentration of oxygen will have no effect on the rate of the reaction. So the reaction is going to remain the same. Okay, so this is the answer to this question. The rate of the reaction will remain the same. That's the end of this problem. And that's the answer to this problem. I hope this was helpful