The standard free energy change for the hydrolysis of ATP to ADP and inorganic phosphate (Pi) is about -30 kJ/mol but in the red blood cell the actual free energy change for this reaction is about -52 kJ/mol. This means that:

a. The concentration of ATP is greater than the product of the concentrations of ADP and Pi.

b. The concentration of ATP is more than 1 M.

c. The product of the concentrations of ADP and Pi is greater than the concentration of ATP.

d. The concentration of inorganic phosphate is much lower that that of ADP.