## Differential and Integrated Rate Laws

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

Ju-Wei Wang 1I
Posts: 31
Joined: Fri Sep 29, 2017 7:05 am

### Differential and Integrated Rate Laws

How do you know when to use a differential rate law versus an integrated rate law? Are there specific things you can look for in the question that direct you to use a certain equation over the other?

Samantha Joseph 1F
Posts: 48
Joined: Fri Sep 29, 2017 7:04 am
Been upvoted: 1 time

### Re: Differential and Integrated Rate Laws

The main difference between differential and integrated rate laws are that differential rate laws are used to describe a reaction rate as a function of the change in concentration over a time period, whereas integrate rate laws show the initial and actual concentration values after a period of time. For example, the differential law means rate = -d[A]/dt, showing that the change in value needs to be provided to answer the question. For integrated (example when n=1), ln[A] = -kt + ln[A0], so you need to know t and the initial and/or final concentration values.

Ridhi Ravichandran 1E
Posts: 35
Joined: Sat Jul 22, 2017 3:01 am

### Re: Differential and Integrated Rate Laws

You use integrated rate laws when you need to find the time or final/initial concentrations. Most problems involve using the integrated rate law; we deal with the differential rate law when we need to find reaction orders, etc.

Diego Zavala 2I
Posts: 65
Joined: Fri Sep 29, 2017 7:07 am
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### Re: Differential and Integrated Rate Laws

For our class most, if not all, problems will use the integrated rate law. The differential rate law is used to derive the integrated rate law