## Slow Step

$aR \to bP, Rate = -\frac{1}{a} \frac{d[R]}{dt} = \frac{1}{b}\frac{d[P]}{dt}$

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### Slow Step

How do we determine which step is the slow step in order to find the correct mechanism?

Rishi_Kayathi_1E
Posts: 24
Joined: Wed Sep 21, 2016 2:59 pm

### Re: Slow Step

The slow step isn't required to find the mechanism. In the mechanism we look for the slowest step and consider it the rate determining step. This is determined by experimentally.

emma_arago_3D
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### Re: Slow Step

If two steps are given in a mechanism, we will also be told whether each step is slow or fast.

Cliff Danza 3F
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### Re: Slow Step

We won't necessarily have to be told which step is the fast or the slow one in a problem. We know that the slow step rate must match the observed rate, which means the first step could be the slow step which would match automatically, or the second step could be the slow step (which causes a bottleneck after the first) and we could show that for a given reaction mechanism through the pre-equilibrium approach as seen in the coursereader page 73.