Nitric Oxide Catalyses

[lizzygaines1D]

For the example in lecture today:
NO+1/2O2---->NO2
NO2---->NO+O
O2+O----->O3
NO is not an intermediate because it is a catalyst. The only way we knew this is because the example was nitric oxide catalyses or is there any other ways to determine which molecule is the catalyst?

[RyanS2J]

You can determine NO is a catalyst from the fact that it is a species that appears as a reactant in an early step and as a product in a later step, indicating that the species is not consumed in the reaction, a fundamental property of catalysts.

[diangelosoriano]

Is there a way to tell by looking at these equations if the catalyst was heterogeneous or homogeneous?

[Michelle Dong 1F]

Catalysts are present in the beginning of the reaction and do not get consumed (so it appears in the products side in the next elementary step), while intermediates are formed in one elementary step and then are consumed in the next elementary step.

[Johann Park 2B]

Is there a way to tell by looking at these equations if the catalyst was heterogeneous or homogeneous?

A catalyst is homogeneous if it is in the same phase as the reactant R.
It is heterogeneous when it is in a different phase as R; in this case it is usually a solid.

[Seth_Evasco1L]

Species that appear in the overall reaction can be ruled out as being the intermediate or catalyst.

An intermediate is produced in one elementary step and then consumed in a subsequent elementary step.

A catalyst is found on the reactants side of one elementary step and also on the products side in another elementary step.

[Michelle Steinberg2J]

An intermediate is formed and then used.
A catalyst is used and then formed.

[smurphy1D]

If NO is the catalyst then what one is the intermediate?