For a binary liquid mixture at 303 K and 4.6 bar, we've calculated the real fluid Gibbs energy in the laboratory to be 1748.1 J/mol, which contains 0.23 mol fraction of Component A, where the pure fluids A and B have Gibbs energies of 1515.6 J/mol and 2652.7 J/mol, respectively; both the pure fluid and real fluid Gibbs energies are calculated with respect to the same reference condition. What is the excess Gibbs energy for this mixture? Report your answer with units of J/mol