## Determining rate order

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

alanaarchbold
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Joined: Fri Sep 28, 2018 12:27 am

### Determining rate order

How do you know which experiments to use in those charts to determine the orders for each reactant?

Chem_Mod
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### Re: Determining rate order

You determine the order of one reactant each time so you want to pick the experiments where the only variation is the concentration of the reactant you are studying.

alanaarchbold
Posts: 68
Joined: Fri Sep 28, 2018 12:27 am

### Re: Determining rate order

Chem_Mod wrote:You determine the order of one reactant each time so you want to pick the experiments where the only variation is the concentration of the reactant you are studying.

But say like in 6th edition 15.19 the solutions use experiments 2 and 3, when the concentration of 2 is equal to the concentration of experiment 1, but the initial rates are different for experiments 1 and 2. Like how would you know to use 2 and 3 instead of 1 and 3, because only 2 and 3 will give you the right answer, but 1 and 2 are the same concentration so why not use 1 and 3?
And then like in 15.17 the concentration for C changes every time but the solutions specifically uses experiments 1 and 4. How did they know to use 1 and 4?

riddhiduggal
Posts: 30
Joined: Fri Sep 28, 2018 12:21 am

### Re: Determining rate order

you can use any of them, but you have to use all the values of that experiment consistently.