Overall reaction order

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

JennyCKim1J
Posts: 51
Joined: Fri Sep 29, 2017 7:04 am

Overall reaction order

Can someone explain what n and m is for the equation

overall reaction order = n + m?

Also, I thought I could determine reaction order by looking at k; is this just another method?

Esin Gumustekin 2J
Posts: 57
Joined: Thu Jul 27, 2017 3:01 am

Re: Overall reaction order

I believe the overall reaction order is the sum of the orders of each reactant in the rate law. I'm not sure what the n and m stand for so I'm confused on that too.

Chem_Mod
Posts: 19176
Joined: Thu Aug 04, 2011 1:53 pm
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Re: Overall reaction order

Hey!
So n and m are the orders with respect to a specific reactant. For example, let's look at a simple reaction: N2 + 3H2 -> 2NH3

Rate = k[N2]^n [H2]^m

n is the order with respect to N2. N2 is nth order for this reaction.
m is the order with respect to H2. H2 is mth order for this reaction.

overall order for the reaction is adding up all the orders for your reaction, so in this case, it's n+m.

Hope this helps! :o