Are These Two Reaction Mechanisms for the Same Reaction?

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The discussion revolves around two proposed reaction mechanisms for the same chemical reaction involving OCl-, H2O, I-, and the formation of OI- and water. The first mechanism has a medium-speed initial step, while the second mechanism features a slow initial step. The key point is that both mechanisms yield the same net reaction, confirming they pertain to the same overall reaction. However, the mechanisms differ in their rate-determining steps, which affects their validity. The rate expression provided, Rate = k[I-], indicates that the concentration of I- influences the reaction rate. To determine which mechanism is correct, one must analyze the rate-determining steps in relation to the rate expression. Not all mechanisms that lead to the same products are valid; the correct mechanism must align with the observed rate law.
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I'm given two reaction mechanisms, both are supposedly for the same reaction and I'm asked to prove it. The reaction mechanisms are:

#1

OCl- + H2O --> HOCl + OH- (medium speed)
HOCl + I- --> HOI + Cl- (slow)
HOI + OH- --> H2O + OI- (fast)

#2

OCl- + H2O --> HOCl + OH- (slow speed)
HOCl + I- --> ICl + OH- (medium)
ICl + 2OH- --> OI- + Cl- + H2O (fast)

I'm guessing that since the original reactants are the same for both and they both form OI- and water as a product, they are the same.. the only difference I can see is that the chlorine ion is separated in a different step, which causes a difference in the rate of that elementary reaction. Also, the rate expression for the final reaction: Rate = k[I-] SHOULD be right, but I'm not sure if it is.. I- seems to be the ion that affects the rate but I'm a little behind on my organic chem so I need some help...thx ahead of time
 
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You are required to prove that they pertain to the same overall reaction ?

In both cases, find the net reaction by simply adding the parts. What do you get ?
 
Oh, sorry, i should of explained more.. there are three parts to the question.. the first is to show that both are for the same reaction, I should of known that, sorry slipped my mind totally to use the net equation... wow lol. Other than that, I am given the rate expression and asked questions about changes such as tripling the I- concentration and such, i do not need help with that. It then proceeds to ask me which mechanism is correct. This i don't understand. How do i figure out which of the mechanisms is correct...if both are for the same reaction, aren't they both correct?
 
No, they won't both be correct. I can make up a bogus mechanism for the same reaction, and it would definitely be wrong. You determine the correct mechanism by looking at the rate equation. According the the opening post, Rate = k[I-] is the given rate equation.

What do you know about rate determining steps ?
 
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