Question

Question #104c0

Answer 1

The Free Energy, calculated using `DeltaG=DeltaH-TDeltaS` tells us whether a reaction is feasible or not, at a certain temperature. If `DeltaG` is positive! the reaction is not feasible.

The Free Energy tells us nothing about how fast the reaction might go, so some reactions might be feasible but proceed at a rate so slow as to not react on an appreciable timescale. This is likely to be because the activation energy for the reaction is very large.

The Activation Energy can't be calculated from the Free Energy, but is a term in the Arrhenius equation, which relates the rate constant, k, for a reaction to the temperature of the reaction, so if you know the rate constant at a certain temperature you can work out the Activation Energy.