units of rates and rate constants


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Saachi_Kotia_4E
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units of rates and rate constants

Postby Saachi_Kotia_4E » Mon Mar 04, 2019 3:19 pm

what are the basic units for rates and rate constants? are they different for different orders?

Chem_Mod
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Re: units of rates and rate constants

Postby Chem_Mod » Mon Mar 04, 2019 3:23 pm

Rate of a reaction is generally monitoring the change in concentration over time, thus M/s. For different order reaction, yes rate constants will vary in units, but rate will not.

Kirsty Star 2H
Posts: 48
Joined: Fri Sep 28, 2018 12:24 am

Re: units of rates and rate constants

Postby Kirsty Star 2H » Mon Mar 04, 2019 4:20 pm

For 0 order reactions, the units for k are M/s, for 1st order reactions, the units for k are 1/s, and for 2nd order reactions the units for k are 1/M*s. With M being molarity or concentration

Kavvya Gupta 1H
Posts: 35
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Re: units of rates and rate constants

Postby Kavvya Gupta 1H » Mon Mar 04, 2019 4:40 pm

for 0 order reaction, k = mol/Ls. For 1st order, k = 1/s. For 2nd order, k = L/(mol s). Overall the units for a reaction should be mol/Ls

lindsey_ammann_4E
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Re: units of rates and rate constants

Postby lindsey_ammann_4E » Tue Mar 05, 2019 10:03 am

The above responses are correct. You can think of dividing the units by moles as you move up to the next order.


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