9. In E. coli., an oxidation-reduction reaction occurs within a cell membrane that pumps protons out of the cell and generates a difference in pH of 1.0 pH unit (pH = 1), with the interior of the cell being higher by the one unit than the exterior. In addition, the reactions result in a difference in membrane potential of -120 mV (interior negative).

(a) How much free energy is available from the oxidation reduction reaction that results in this pH and potential difference? (assume temperature is 25C)

(b) If the movement of the molecule, galactose, is coupled to the free energy generated by the above oxidation-reduction reaction, what is the maximum internal to external galactose ratio that can be obtained, assuming the galactose is being pumped against a concentration gradient? (assume that galactose is being symported with the H+ ).