Question

Which of the following does a positive change in the Gibbs free-energy value represent?

a spontaneous reaction

a nonspontaneous reaction

a reaction at equilibrium

an exothermic reaction

Answer 1

∆G has to do with reaction spontaneity.

for a reaction to occur spontaneously, the free energy of the products must be lower than the free energy of the reactants. if the free energy of the products is higher than that of the reactants, the reaction is nonspontaneous.

∆G is the free energy of products minus the free energy of reactants. so there you go.