Determining Order  [ENDORSED]


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Paula Dowdell 1F
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Joined: Tue Nov 15, 2016 3:00 am

Determining Order

Postby Paula Dowdell 1F » Thu Mar 01, 2018 10:47 pm

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

DianaTrujillo2K
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Joined: Fri Sep 29, 2017 7:04 am

Re: Determining Order

Postby DianaTrujillo2K » Thu Mar 01, 2018 10:55 pm

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

Lucia H 2L
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Re: Determining Order

Postby Lucia H 2L » Thu Mar 01, 2018 11:42 pm

How do you find orders of the reactants?

Mika Sonnleitner 1A
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Re: Determining Order

Postby Mika Sonnleitner 1A » Thu Mar 01, 2018 11:45 pm

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
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Re: Determining Order

Postby Hena Sihota 1L » Fri Mar 02, 2018 1:14 am

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
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Joined: Fri Sep 29, 2017 7:05 am

Re: Determining Order

Postby Xin He 2L » Fri Mar 02, 2018 1:23 am

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

Emily Mei 1B
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Re: Determining Order

Postby Emily Mei 1B » Fri Mar 02, 2018 1:19 pm

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

404995677
Posts: 82
Joined: Fri Sep 29, 2017 7:07 am

Re: Determining Order

Postby 404995677 » Fri Mar 02, 2018 5:29 pm

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

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

Mitch Walters
Posts: 45
Joined: Fri Sep 29, 2017 7:07 am

Re: Determining Order  [ENDORSED]

Postby Mitch Walters » Fri Mar 02, 2018 7:12 pm

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.


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