Another proposed mechanism problem:
H2O2 + I ---> H2O +IO slow
H2O2 + IO ---> H2O + O2 + I fast
Which of the following statements in incorrect?
a.) IO is a catalyst
b.) I is a catalyst
c.) The net reaction is 2H2O2 ---> 2H2O + O2
I would choose B, since IO is shown as both a product and reactant, but I don't know if my reasoning is correct.
To determine which statement is incorrect among the given options, we need to analyze the proposed mechanism and the overall reaction.
The proposed mechanism involves two steps: a slow step where H2O2 reacts with I to form H2O and IO, and a fast step where H2O2 reacts with IO to form H2O, O2, and I.
Let's break down the proposed mechanism and the overall reaction:
Step 1: H2O2 + I ---> H2O + IO (slow)
Step 2: H2O2 + IO ---> H2O + O2 + I (fast)
Based on Step 1, IO is formed as a product when H2O2 reacts with I. This means IO is not a catalyst in this step. IO is being consumed rather than regenerated, so it cannot be considered a catalyst.
Based on Step 2, IO is involved in a fast step where it reacts with H2O2 to form H2O, O2, and I. This means IO is being consumed as a reactant in this step and cannot be considered a catalyst.
Now, let's consider the options provided:
a) IO is a catalyst.
As explained above, IO is not a catalyst since it is consumed in both steps of the mechanism.
b) I is a catalyst.
Based on the proposed mechanism, I is not involved as a catalyst. I is neither produced nor consumed in the mechanism.
c) The net reaction is 2H2O2 ---> 2H2O + O2.
We can obtain the net reaction by summing up the two steps of the mechanism:
H2O2 + I + H2O2 + IO ---> H2O + IO + H2O + O2 + I
Canceling out the common species, the net reaction simplifies to:
2H2O2 ---> 2H2O + O2
This means option c is correct.
Therefore, the incorrect statement among the given options is b) I is a catalyst.