Catalysts

[Matthew ILG 1L]

In today's lecture(3/9/20) Dr. Lavelle gave an example of how Nitric Oxide catalyses the conversion of oxygen to ozone in lower atmosphere.
He stated that NO(g) is a catalyst. However, is O2(g) also a catalyst?
It is not formed at any point during the process, so I assume it is not an intermediate.

[Jasmine Fendi 1D]

I do not think that O2 is a catalyst, but rather just part of the reaction. The intermediates are NO2 and O, while the only catalyst is NO.

[Amy Pham 1D]

O2 is not a catalyst, simply a reactant in the overall reaction. The process itself refers to the conversion of oxygen to ozone, so oxygen is a simply a reactant in this process, otherwise there would be no reactants. So yes, nitric oxide (NO) is the only catalyst in this reaction.

[Kallista McCarty 1C]

Nitric oxide (NO) is the only catalyst. The O2 is just a reactant

[105335337]

NO is the only catalyst and O2 is simply just a reactant because it is not reformed in the products.

[BCaballero_4F]

From my understanding in lecture, the catalyst in this reaction is NO, not O2

[kristi le 2F]

Dr. Lavelle also noted the difference between intermediates and catalysts in which catalysts are initially there and then reformed while intermediates are created and consumed in the reaction.

[Hamna_Khan_2E]

Hi!

In the example you provided, Nitric Oxide (NO) catalyzes the conversion of Oxygen (O2) to Ozone (O3) in the lower atmosphere. O2 is not a catalyst since it does not participate in the catalytic cycle. It must be involved in a reaction cycle in which it is both consumed and regenerated in order to be termed a catalyst. In this reaction, NO is consumed in the initial step to make NO2, which subsequently interacts with O2 to produce NO and O3. Thus, NO is regenerated and available to catalyze the reaction again at the conclusion of the cycle. In contrast, O2 does not participate in the reaction cycle and is neither consumed nor produced during the conversion of O2 to O3. It is simply a reactant in the overall reaction.

Hope this helps!