## stoichiometry

$\frac{d[R]}{dt}=-k[R]; \ln [R]=-kt + \ln [R]_{0}; t_{\frac{1}{2}}=\frac{0.693}{k}$

katherinemurk 2B
Posts: 68
Joined: Wed Nov 15, 2017 3:02 am

### stoichiometry

How does stoichiometry come into kinetics? There are some questions in the book that ask about finding k constants when they give you the initial concentration of A but then give you a concentration of B at the some point in time?

Samantha Man 1L
Posts: 63
Joined: Fri Sep 28, 2018 12:22 am

### Re: stoichiometry

For those problems, you have to set up an ICE box in order to find your final concentrations of [A] given the change in concentration of [B] so that you can plug it into the integrated rate laws for the respective orders.

Laurence Tacderas 1K
Posts: 30
Joined: Fri Sep 28, 2018 12:20 am

### Re: stoichiometry

There may be problems where you need the final concentration of A to solve for the rate constant k or the time, but you are only given the final concentration of B. So then, given a balanced chemical equation, you would convert that final concentration in terms of A using stoichiometry.