In the reaction mechanism below, indicate what substance is acting like a catalyst.
Step 1: H2O2 (aq) + I- (aq) → H2O (l) + IO- (aq)
Step 2: H2O2 (aq) + IO- (aq) → H2O (l) + I- (aq)
Is the catalyst in the problem above a heterogeneous or a homogeneous catalyst?
I think that step 2 is the catalyst which leads me to believe that it is homogeneous, am I correct?
Thanks.
To determine the catalyst in the given reaction mechanism, we look for a substance that appears in the reactants of one step and reappears in the products of another step without being consumed in the reaction.
In this case, iodide ions (I-) are present in the reactants of Step 1 and reappear in the products of Step 2. Since iodide ions are not consumed during the reaction and facilitate the conversion of reactants into products, they act as a catalyst.
Now, let's determine if the catalyst in this reaction is a heterogeneous or homogeneous catalyst.
A heterogeneous catalyst exists in a different phase than the reactants and products, while a homogeneous catalyst exists in the same phase.
In this case, since both H2O2 and the iodide ions (I-) are dissolved in an aqueous solution, the catalyst is a homogeneous catalyst because it exists in the same phase as the reactants and products.