Catalyst vs. Intermediate

[Tinisha 1G]

Can someone explain how I would differentiate a catalyst from an intermediate in a reaction?

[Jerome Mercado 2J]

A catalyst is a reactant first in the mechanism and then a product:

C + D ==> E (fast)

E ==> F + D (fast)

D is a catalyst

An intermediate is the opposite; it is a product first and then a reactant afterwards:

A + B ==> C (slow)

C + D ==> E (fast)

C is an intermediate

[bonnie_schmitz_1F]

An intermediate is something formed in a reaction and then used up later. A catalyst is present at the beginning of the reaction.

[Yvonne Du]

A catalyst is involved in the starting of the reaction, while an intermediate joins in later. Both of them are not included in the rate law.

[LaurenJuul_1B]

an intermediate is formed and then used up in the reaction

a catalyst is there the whole time and is not used up in the reaction

[bonnie_schmitz_1F]

A catalyst is involved in the starting of the reaction, while an intermediate joins in later. Both of them are not included in the rate law.

Today, my TA said that a catalyst can be included in the rate law. Can someone clarify?

[Yvonne Du]

A catalyst is involved in the starting of the reaction, while an intermediate joins in later. Both of them are not included in the rate law.

Today, my TA said that a catalyst can be included in the rate law. Can someone clarify?

Sorry! I made a mistake. Yes it is possible for a catalyst to appear in the rate law, but it is not included in the chemical equation.

[805169754]

You can find a catalyst in the beginning of the reaction and at the end whereas an intermediate is produced and consumed during the reaction.

[Nicholas Le 4H]

A catalyst can be found in the beginning of the reaction, while an intermediate is found in the later steps.