4(36) Why z Gibbs Activation always + for reactions

Moderators: Chem_Mod, Chem_Admin

Kiara1F
Posts: 64
Joined: Fri Sep 25, 2015 3:00 am

4(36) Why z Gibbs Activation always + for reactions

Postby Kiara1F » Fri Mar 03, 2017 1:45 pm

Can someone explain problem 4(36) in the Intro to Organic Chem book... Why is the standard Gibbs free energy of activation always a positive value?
I thought - value was spontaneous.. and therefore favorable ( or does that have nothing to do with this?)

Jerry Wang 1L
Posts: 10
Joined: Fri Jul 22, 2016 3:00 am

Re: 4(36) Why z Gibbs Activation always + for reactions

Postby Jerry Wang 1L » Fri Mar 03, 2017 6:21 pm

Hello,

The Gibb's free energy is always going to be positive for the energy of activation because by definition, energy must be pumped into the system in order to overcome that energy barrier (or else it wouldn't be called energy of activation if it happened by itself!). Suppose that the Gibb's free energy is negative, then I agree with you that it will be spontaneous in that case but that would defeat the purpose of having an energy of activation because the energy of activation is what limits a reaction from proceeding forward.


Return to “*Free Energy of Activation vs Activation Energy”

Who is online

Users browsing this forum: No registered users and 1 guest