## Arrhenius Equation [ENDORSED]

Arrhenius Equation: $\ln k = - \frac{E_{a}}{RT} + \ln A$

William Lan 2l
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### Arrhenius Equation

When do you use the Arrhenius Equation?

Sara Sasaki 1K
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### Re: Arrhenius Equation

You can use the Arrhenius equation to show the effect a change of temperature has on the rate constant (and thus the reaction as well). Hope this helps!

Sammy Thatipelli 1B
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### Re: Arrhenius Equation

To be add on for when we use the Arrhenius Equation, it is clear we need to use it if we are working with the Boltzmann distribution e^-Ea/R, which gives the fractions of collisions wth energy,Ea, or greater temp at T. In this case, A would be the frequency factor or pre-exponential factor (includes #collisions with correct orientation).

Arrhenius Equation with Graphs:

If you are working with a graph, you use Arrhenius Theory by looking at the plot of lnk vs. 1/T. then the plot will be linear with the slope m=-Ea/RT.

Yu Chong 2H
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### Re: Arrhenius Equation

Whenever you see a kinetics question that involves temperature change, you're most likely gonna use the Arrhenius equation.

Irma Ramos 2I
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### Re: Arrhenius Equation

When using the Arrhenius Equation, are we always going to use it in the form k=... or are we going to have to know how to re-arrange it and solve?

Chem_Mod
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### Re: Arrhenius Equation  [ENDORSED]

Definitely need to know how to re-arrange it and solve for Ea. See HW problems.

Masih Tazhibi 2I
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### Re: Arrhenius Equation

I have heard that when plugging in values for Ea, you want to convert the units to joules, or else your answer will be incorrect. Is this because R is in J/mol*k?

Michael Cheng 1C
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### Re: Arrhenius Equation

how would you find A (frequency factor) in the Arrhenius Equation?