Suppose we are doing heterogeneous catalysis, for example, between nitrogen and hydrogen to create ammonia in the presence of a solid catalyst, like rhuthenium. It's obvious that the gas molecules don't "collide" directly and, therefore, the Arrhenius equation does not completely apply. Does a modified version of the equation exist that takes this into account?

My guess would be that since catalysts generally decrease the activation energy of a reaction, the activation energy value would possibly have a fractional component to it. Furthermore, because the reaction is occurring on a surface, the decreased direct collisions may affect the rate. I would greatly appreciate it if someone could point me in the right direction.

  • 1
    $\begingroup$ Being catalyzed is not the major modification factor. The major factor is becoming a reaction on solid surface, instead in free volume. $\endgroup$
    – Poutnik
    Oct 29, 2021 at 6:02
  • $\begingroup$ I would start with the 2D model of the multistep reaction mechanism, each step having its own activation energy. ( so does not catalyzed reaction if free space ) $\endgroup$
    – Poutnik
    Oct 29, 2021 at 9:41


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.