A critical reaction in the production of energy to do work or drive chemical reactions in biological systems is the hydrolysis of adenosine triphosphate, ATP, to adenosine diphosphate, ADP, as described by ATP(aq) +H2O(l)=ADP(aq)+HPO2-/4(aq) for which ?G°rxn = -30.5 kJ/mol at 37.0 °C and pH 7.0. Calculate the value of ?Grxn in a biological cell in which [ATP] = 5.0 mM, [ADP] = 0.20 mM, and [HPO42-] = 5.0 mM.