## Transition States

$K = \frac{k_{forward}}{k_{reverse}}$

Alyssa McLeod 3E
Posts: 13
Joined: Wed Sep 21, 2016 2:59 pm

### Transition States

Could someone explain the difference between transition states and intermediates? Thanks!

Pauline Tze 3B
Posts: 57
Joined: Sat Jul 09, 2016 3:00 am
Been upvoted: 1 time

### Re: Transition States

Transition states are at the top of the "humps" of your energy profile diagram and intermediates are in the "valleys." Both are unstable, but transition states are more unstable than intermediates because they have more energy (from distorted/partial bonds).
In the context of the material we have learned, you can have transition states in both electrophilic addition and SN2 but you can only have intermediates in electrophilic addition.
hope that helps!

Uisa_Manumaleuna_3E
Posts: 10
Joined: Wed Sep 21, 2016 2:56 pm

### Re: Transition States

Another way you can look at the differences between transition states and intermediates is in their role when it comes to writing out reaction mechanisms.

Transitions states, when drawn out in mechanisms, usually show whatever compounds and elements in the reaction are reacting with one another and exchanging electrons to bring out the final products. In transition states, we can see the change happening...

...While intermediates don't necessarily undergo that change. Rather they are just products in the first reaction step and become reactants in the next. They still play a role in the progress of the reaction, but unlike transition states, they don't necessarily encompass that entire change. Rather, they're just part of what change occurs.

Hope this helps!