## initial rate law

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

Emma Li 2C
Posts: 51
Joined: Fri Sep 29, 2017 7:07 am
Been upvoted: 1 time

### initial rate law

Is it always only the reactant concentrations that affect the rate law?

Thank you!

Jeremiah Samaniego 2C
Posts: 33
Joined: Fri Sep 29, 2017 7:05 am

### Re: initial rate law

For ease of analysis, we want to study specifically the initial concentrations of reactants, because as the reaction progresses, the presence of products could affect the interpretation of the reaction rate.

Diego Zavala 2I
Posts: 65
Joined: Fri Sep 29, 2017 7:07 am
Been upvoted: 1 time

### Re: initial rate law

Because the rate law would become more complicated if we were to analyze the rxn when the presence of products is significant, we only consider the reaction at the very beginning when the amount of products can be considered negligible. While products also affect the rate law, we consider the rate law at a domain where it remains insignificantly affected by the concentration of products

Ramya Lakkaraju 1B
Posts: 67
Joined: Fri Sep 29, 2017 7:03 am

### Re: initial rate law

The more accurate method would be to analyze changes in both the reactant and product concentrations.

Sally Nason - 1K
Posts: 40
Joined: Fri Sep 29, 2017 7:05 am

### Re: initial rate law

Also in a lot of the homework problems, you use the change in the concentration of the product to find the change in the concentration of the reactant.