Delta G Double Dagger, Delta H Double Dagger, Delta S Double Dagger

[Vera Ong 3H]

Conceptually, why are delta G double dagger and delta H double dagger values always positive? Why could delta S double dagger be positive or negative? What are examples of situations for pos/neg situations for delta s double dagger?

[mikezargari]

I'm pretty sure that the delta G and delta H double daggers are always going to be positive because they represent the amount of energy that is needed to overcome the activation barrier. If you have a reaction A+B->AB(double dagger)->C energy is required to first break the bonds of A and B so that they can react with one another hence the delta H double dagger's positive sign. Hope this helped.

[Ariana de Souza 4C]

And I'm pretty sure you have delta S as negative because you're making the molecule into one particular orientation for it to be a transition state, so there is a decrease in entropy. I don't know why you would have a positive delta S though...

[Josephine_Tang_1N]

If this is referring to Section 4.4 in the green organic textbook, they state that all the statements they make reference the reaction in Figure 4.6, which is an SN2 reaction.