Hi guys
I'm having trouble with this question:
Ammonia gas is formed in the combustion of biomass fuels and is a significant
pollutant when it is released directly into the atmosphere. One method of removing
this ammonia involves its oxidation using a titanium(IV) oxide catalyst.
The best explanation for the use of titanium(IV) oxide is that the titanium
(A) contains many active sites on which the reaction can occur.
(B) is readily oxidized to a higher oxidation state which can then be reduced back
to oxidation state +4.
(C) is readily reduced to a lower oxidation state which can then be oxidized back
to oxidation state +4.
(D) has partially filled d orbitals in its +4 oxidation state.
The answer is C according to the mark scheme.
I was originally under the impression that homogenous catalysts are catalysts which are chemically changed during the reaction (forming intermediates), and heterogenous catalysts are those which function via surface activity (adsorption of reactants, desorptions of products etc.). For that reason, I put A. Clearly my reasoning is flawed.
Can anyone explain why the answer is C?
Thank you
.