rate constants


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Rebecca Doan 2L
Posts: 51
Joined: Thu Jul 27, 2017 3:01 am

rate constants

Postby Rebecca Doan 2L » Sun Feb 25, 2018 10:40 pm

how are rate constants calculated and what do they represent?

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

Re: rate constants

Postby DianaTrujillo2K » Sun Feb 25, 2018 10:43 pm

A rate constant represents how fast a chemical reaction will take place based on the concentrations of the reactants and products. You find it by plugging in the molar concentrations into your rate equation with their respective order and equaling it to the rate of the reaction.

Lisa Tang 1C
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Re: rate constants

Postby Lisa Tang 1C » Sun Feb 25, 2018 10:48 pm

In addition to what is stated above, the rate constant k is independent of the concentrations of the reactants. You would multiply k by the concentrations to find the rate, but the concentrations themselves do not impact k.

Nathan Tu 2C
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Joined: Fri Sep 29, 2017 7:07 am

Re: rate constants

Postby Nathan Tu 2C » Sun Feb 25, 2018 10:52 pm

I would also like to add that k has different units for each type of order reaction. For example, k is in M/Ls for zero order equations and inverse seconds for first order equations. To find the units for k, set the reaction equal to M/Ls and solve for whatever units allow the units to end up as M/Ls

Kayla Tchorz-Dis 1F
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Joined: Thu Jul 13, 2017 3:00 am

Re: rate constants

Postby Kayla Tchorz-Dis 1F » Mon Feb 26, 2018 9:36 am

I'm also a little confused on the concept of K. In our notes it says K is dependent on temperature and activation energy. So if it's dependent, how is it a constant?

Lisa Tang 1C
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Re: rate constants

Postby Lisa Tang 1C » Mon Mar 05, 2018 9:59 pm

Kayla Tchorz-Dis 1F wrote:I'm also a little confused on the concept of K. In our notes it says K is dependent on temperature and activation energy. So if it's dependent, how is it a constant?

The rate constant is constant in that it won't change under those specified conditions.

Harjas Sabharwal 1G
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Joined: Sat Jul 22, 2017 3:01 am

Re: rate constants

Postby Harjas Sabharwal 1G » Tue Mar 06, 2018 1:07 am

the rate constant is constant for a specific reaction at a specific temperature. If the reaction is different then the activation energy would be different, and if the temperature is different then that would influence K as well.

Sarah 2F
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Joined: Fri Sep 29, 2017 7:06 am

Re: rate constants

Postby Sarah 2F » Fri Mar 09, 2018 10:34 pm

They calculate the speed of the reaction


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