## Determining Overall Reaction Rate

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

Simone Seliger 1C
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### Determining Overall Reaction Rate

When there are two of the same molecules as the reactants of a reaction, they are written [A][A], which equals [A]^2. This would make the reaction second-order. However, if there are 2 different molecules, the reaction would be [A]^1[B]^1. Does this make it an overall first-order reaction?

Beata_Vayngortin_3L
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### Re: Determining Overall Reaction Rate

To determine the overall order of the reaction, you have to add the individual reaction rates so I believe this would make your overall reaction a second order reaction because A is first order and so is B in this example.

Chem_Mod
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### Re: Determining Overall Reaction Rate

In the case of [A][B], the overall reaction is 2nd order because the sum of the exponents is 2. However, the reaction is 1st order in reagent A and 1st order in reagent B. In the case of [A]^2, the reaction is 2nd order overall and 2nd order in reagent A.

Samuel_Vydro_1I
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Joined: Fri Jul 22, 2016 3:00 am

### Re: Determining Overall Reaction Rate

Such as when given a question regarding a table of values (COncentrations, Rates, Etc.) and you are asked to find the order of each substance and the overall order. It is important to remember to add the overall exponents at the end to find overall rate. Each individual order only relates to the specific reactant.