## Activation Energies

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

Goyama_2A
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### Activation Energies

Are activation energies always constant? If not, what variables change them?

Chem_Mod
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### Re: Activation Energies

You can change the activation energy of a reaction by adding a catalyst; this provides an alternative pathway for the reactants to form products that has a lower energy barrier

Ipsita Srinivas 1K
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### Re: Activation Energies

No, activation energies are not constant. Catalysts are a good example of this, as they increase reaction efficiency by lowering activation energy (sometimes), requiring less energy for the reaction to take place. They do so by stabilising the transition state between reactant and product.
However, for most reactions, we can assume the activation energy to be constant unless said otherwise.

Goyama_2A
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### Re: Activation Energies

So, is a condition of a reaction having "arrhenius behavior" having constant activation energy?

205291012
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Joined: Mon Nov 11, 2019 12:17 am

### Re: Activation Energies

No activation energies are not always constant. If you add a catalyst, it tends to lower the activation energy and thus the reaction can progress faster