Determining Order [ENDORSED]

[Paula Dowdell 1F]

Can someone explain to me how to determine what kind of order a reaction is? Thanks.

[DianaTrujillo2K]

To determine the order of the overall reaction you add the orders of the reactants.

[Lucia H 2L]

How do you find orders of the reactants?

[Mika Sonnleitner 1A]

The order of the reactants should be given in the problem in some form. The problem will either explicitly state "first order reactant" and "second order reactant", or give some other type of information that would help you determine the order. For example, the problem could state that the graph of ln(concentration) vs. time is linear, so you can determine that the reactant is first order. Additionally, the problem could give you units of k, which helps determine the order of the reaction. Overall, the problem would have to give you some sort of indication as to what the order of the reactants are.

[Hena Sihota 1L]

Additionally, example 15.2 in the textbook explains how to find the order of the reactants and the order of the overall reaction if you're given a table of experimental data.

[Xin He 2L]

Page 619 includes a lot of helpful information on the orders of the reactions.

[Emily Mei 1B]

The first few homework problems are also solid practice for determining reaction order.

[404995677]

I think a good way to start is to create a graph if you are given a chemical equation and different experimental data.

like this one.

Then, you use the data (like we did in class) to determine the reaction order of each reactant.

[Mitch Walters]

You have to to experiment by looking at how much the rate changes from your initial amount. If it changes by double it is a first order. If it quadruples it is second order. The important thing to note is that it has nothing to do with the coefficients of your chemical equation.