More alkyl groups you're attached to means you are more energetically

[Kurokari]

In alkenes, the more alkyl groups you're attached to means you are more energetically stable, and that we know the reactivity increases as the stability of the intermediate carbocation increases (with tertiary the most stable)

I'm puzzled by this relationship, how is it that when it is more stable, the reactivity increases.

I suspect that it is because when a primary carbocation is less stable, it tends to revert back to its previous form, thus deterring the reaction while a tertiery carbocation is more readily formed and react with other substances.

I would appreciate it deeply if anyone who can clear my doubts :)

EDIT: There was a mention that the stability of the intermediate ions governs the activation energy for the reaction. (It would be nice to explain this line too!)

 

[DrDu]

Maybe you can formulate your question more clearly. First you mention stability of alkenes, then you talk of carbocations and then you are taking about some unspecified reaction.
For some basic chemical kinetics, this article in wikipedia may be a starting point:
http://en.wikipedia.org/wiki/Transition_state_theory

 

[Kurokari]

I'm sorry for the poorly-phrased question, give me another try at this.

An intermediate ion with tertiary carbocation is the most stable right? This is because it has the most alkyl group attached to it, thus making it stable.

There is also a mention that the more stable the intermediate ion(that is the tertiary carbocation in this case) is, the better the reactivity(means the faster it reacts). I'm confused how is it that a more stable compound can be more reactive.

Also there is a line that says that the intermediate ion governs activation energy, I feel that this line may help me understand my question better, however I fail to see any significant relationship between the activation energy and the intermediate ion.

I hope this is better.

 

[DrDu]

I asked you to specify the reaction you have in mind. I suppose you are taking about some reaction of an alkene with an electrophilic.

An intermediate ion with tertiary carbocation is the most stable right? This is because it has the most alkyl group attached to it, thus making it stable.

Yes

There is also a mention that the more stable the intermediate ion(that is the tertiary carbocation in this case) is, the better the reactivity(means the faster it reacts). I'm confused how is it that a more stable compound can be more reactive.

The point is not that the carbocation reacts more rapidly but that it is formed more rapidly which is the step which limits the velocity of the reaction.

 

[LudusRex]

I can provide some clarification on this concept. In organic chemistry, the stability of a molecule or intermediate ion is determined by its electronic structure and the distribution of electrons within the molecule. Alkyl groups, which are hydrocarbon chains, are known to have a stabilizing effect on molecules due to their electron-donating nature.

In the case of alkenes, the more alkyl groups that are attached to the double bond, the more stable the molecule becomes. This is because the alkyl groups donate their electrons to the double bond, making it more difficult to break and increasing the overall stability of the molecule.

Now, when it comes to reactivity, it is important to understand that reactions occur when molecules can lower their overall energy, which is referred to as the activation energy. In the case of alkenes, the addition of alkyl groups increases the stability of the intermediate carbocation, which in turn lowers the activation energy for the reaction. This means that the reaction can occur more easily and at a faster rate.

In simpler terms, the stability of the intermediate carbocation determines how easily a reaction can occur. A more stable intermediate means a lower activation energy, and therefore a higher reactivity. This is why tertiary carbocations, which are the most stable, are the most reactive.

I hope this helps to clarify the relationship between stability and reactivity in alkenes. If you have any further questions, please feel free to ask.