Rate Law vs. Rate of reaction  [ENDORSED]


Moderators: Chem_Mod, Chem_Admin

Sophia Kim 1C
Posts: 51
Joined: Fri Sep 29, 2017 7:04 am
Been upvoted: 1 time

Rate Law vs. Rate of reaction

Postby Sophia Kim 1C » Wed Mar 07, 2018 1:52 am

I'm a bit confused on the difference between the rate of reaction, which is the change in the concentration of a species over change in time and rate law?
Rate law seems to be the same idea so i'm a bit confused.

Chem_Mod
Posts: 18716
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 631 times

Re: Rate Law vs. Rate of reaction  [ENDORSED]

Postby Chem_Mod » Wed Mar 07, 2018 7:54 am

The rate law and the rate of reaction are different. The rate of reaction (in terms of disappearance of reactant A) is -d[A]/dt.

The rate law relates the rate to an expression involving the rate constant k and the initial concentrations of reactants. The rate law for A + 2B --> C is:

rate = k[A][B]^2

assuming that A + 2B --> C is an elementary reaction. If it is not, the exponents will need to be determined experimentally.

The rate is usually the unique rate.


Return to “General Rate Laws”

Who is online

Users browsing this forum: No registered users and 3 guests