### Order of Reaction

Posted:

**Sun Mar 08, 2020 11:17 pm**How do you determine if a reaction is zero, first, or second order? Is there a way to tell without looking at a graph?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=147&t=61700

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Posted: **Sun Mar 08, 2020 11:17 pm**

How do you determine if a reaction is zero, first, or second order? Is there a way to tell without looking at a graph?

Posted: **Sun Mar 08, 2020 11:22 pm**

The way to tell if a reaction is a zero order reaction is when the rate is unaffected by the concentration of the reactants. First order reactions rate changes linearly based on 1 reactant concentration.

Posted: **Mon Mar 09, 2020 10:39 am**

By looking at the rate law, a 0 order equation with be the simplest looking [A]= -kt + [A]. The first order equation always has ln before [A] so , ln[A]= -kt + ln[A]. Finally 2nd order has [A] in a fraction over 1, so 1/[A]= kt + 1/[A].

Posted: **Mon Mar 09, 2020 10:44 am**

Yes, by comparing equations with rates and concentrations for different experiments as we did in class you can find the exponents for the differential rate laws and the exponent directly corresponds to the order of the reaction.