Question

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)+H20(l)-->ADP(aq)+HPO4^2-(aq) for which Delta G°rxn = –30.5 kJ/mol at 37.0 °C and pH 7.0. Calculate the value of Delta Grxn in a biological cell in which [ATP] = 5.0 mM, [ADP] = 0.60 mM, and [HPO42–] = 5.0 mM.

Answer 1

delta G rxn = dGo + RTlnQ where
Q = (ADP)(HPO4^2-)/(ATP)

Answer 2

Watch the units. dGo part in kJ and +RTlnK part in J