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Does anyone have a good method or explanation of the effect of temperature on endothermic and exothermic reactions?

Started about 2 years ago by Ryan Johnson.



3 Comments

  • Adrian Dingle

    Posted about 2 years ago

    See this post for Feb 2014; https://www.adriandingleschemistrypages.com/ap/why-does-increasing-t-speed-the-endo-direction-more-than-the-exo/

  • Kimberly Duncan

    Posted about 2 years ago

    PhET (https://phet.colorado.edu/) has a great simulation called Reversible Reactions that can be used in a variety of ways. You can watch a reaction proceed over time and observe what happens at the particle level for endo and exothermic reactions. The sim allow you to change the temperature and watch what happens to the rate of the reaction. You can also change activation energy and the concentration of the reactant and product particles at the beginning of the reaction. The simulation shows what happens at the particle level as a reaction proceeds.

  • Kaleb Underwood

    Posted about 2 years ago

    Is this referring to equilibrium? If so, the endothermic direction of a reversible process always has a higher activation energy than the exothermic direction.

    Temperature increases always have a greater effect on the endothermic reaction of a reversible process. Initially, very few particles have enough energy to surpass the large Ea. Thus, there is a large bank of ineffective collisions that could be made effective. Since the number of effective collisions is so small compared to ineffective collisions, it doesn't take a terribly large increase to have a large effect in terms of a ratio.

    In an exothermic process, when Ea is small, most collisions are already effective at producing products. Therefore, any increase in the number of successful collisions will not have a large effect in terms of changing the ratio of successful collisions to unsuccessful collisions.