## H.W. Problem 15.17

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

Nandhini_2K
Posts: 60
Joined: Fri Apr 06, 2018 11:03 am

### H.W. Problem 15.17

Part A asks to calculate the order for each reactant.

The solution Manuel uses experiment 2 and 3 to solve for the order with respect to B. Why can't we use experiment 1 and 2?
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sharonvivianv
Posts: 63
Joined: Fri Apr 06, 2018 11:05 am

### Re: H.W. Problem 15.17

Experiments 1 and 2 would help you get the order for [A] but not for [B] because the concentrations are the same in both equations.

Nandhini_2K
Posts: 60
Joined: Fri Apr 06, 2018 11:03 am

### Re: H.W. Problem 15.17

Also why don't we calculate the order for reactant C?

sharonvivianv
Posts: 63
Joined: Fri Apr 06, 2018 11:05 am

### Re: H.W. Problem 15.17

If you look at experiments 1 and 4, you see that concentrations for C change but the initial rates are both 2. This means that C is independent of the rate.

Chem_Mod
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### Re: H.W. Problem 15.17

In general, it's a good idea to start with the pairs of experiments where only one reactant's concentration is changing while the other concentrations are held constant. Looking at experiments 1 and 2, we see that both [A] and [C] are changing.

Hope this helps! :)

He whose name cannot be spoken
Posts: 20
Joined: Sat Apr 28, 2018 3:00 am

### Re: H.W. Problem 15.17

Nandhini_2K wrote:Also why don't we calculate the order for reactant C?

You can, it's just not gonna be very useful