please answer b-d

2. Given the following groundwater composition: lon Conc. (mg/L) Ca2+ 75 Mg2+ 40 Na 10 SO42- 110 CI 10 HCO3 300 (a) Compute the ionic strength for this water. (b) Determine the activity coefficients for Nat and SO42- using the Davies equation (C) If the pH of the water is 8.0 and temperature is 25 C, calculate the activity of Ca 2+ assuming it is in equilibrium with calcite based on the stoichiometry given in Problem 1. Use the ionic strength for the water calculated in part (a) and Pco2 = 10-3.5 atm (Assume there is no need to correct the partial pressure for activity). (d) Compare the value for Ca2+ activity calculated in (c) to that determined from the table to evaluate whether the system is at equilibrium with CaCO3(s). If not, which direction would the reaction proceed