## Elementary Steps

$V_{0} = \frac{V_{max}[S]}{K_{M} + [S]}; K_{M} = \frac{[E][S]}{[ES]}$

lizettelopez1F
Posts: 29
Joined: Fri Sep 28, 2018 12:19 am

### Elementary Steps

Why can we not add the cell potential of elementary steps?

Chem_Mod
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### Re: Elementary Steps

I think what you're referring to is that when you have to calculate the E value for a reaction like this: Ti+4 + 2e- -> Ti+2, you cannot simply add the E values for the reactions Ti+4 + e- -> Ti+3 and Ti+3 + e- -> Ti+2.

The details about why this happens aren't too important, but this is a good general rule: If the reaction you're calculating the E value for has electrons in it, you cannot simply add the E values from the 2 reactions needed to make that reaction. If the reaction you're calculating the E value for does not have electrons in it, you can simply add the E values. :)

Kassidy Ford 1I
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### Re: Elementary Steps

Also, cell potential only refers to electrochemistry, more specifically redox reactions. In kinetics, elementary steps are used to find the reaction mechanism that matches the rate law... they usually wont have a given cell potential as these are usually not reduction or oxidation reactions.