## Catalysts vs Intermediates

Arrhenius Equation: $\ln k = - \frac{E_{a}}{RT} + \ln A$

YashDeshmukh1D
Posts: 42
Joined: Fri Sep 29, 2017 7:05 am

### Catalysts vs Intermediates

When given the elementary steps of a reaction, both intermediates and catalysts are cancelled out when writing the overall reaction. In problems like 15.71, how can you tell if a cancelled out species is an intermediate or a catalyst?

Justin Lai 1C
Posts: 50
Joined: Fri Sep 29, 2017 7:04 am

### Re: Catalysts vs Intermediates

The catalyst usually appears in the beginning of the reaction and the end of the reaction. So if it is consumed, it will reappear in the end. The intermediate does not appear in the beginning or the end of the reaction-it is both formed and consumed in the middle of the reaction.

Meredith Steinberg 2E
Posts: 50
Joined: Thu Jul 13, 2017 3:00 am

### Re: Catalysts vs Intermediates

Intermediates are produced in one of the elementary steps, and consumed in another, thereby cancelling it out. Catalysts, however, are not produced in between and are at the beginning of the reaction and are at the end of the elementary steps to cancel out.