Question

What effect does catalyst have on gibbsenergy of a reaction?

Answer 1

A catalyst does not have any effect on the Gibb's free energy of a reaction.
Gibb's free energy of the reaction is the energy difference between the inital state (reactant) and final state (product) of the reaction. A A catalyst only lowers the activation energy and increases the rate of the reaction. It does not affect the energy of either the reactant or product.