for the following, mix the equal volumes of one solution from group I with one solution from group II to achieve the indicated pH. calculate the pH of each solution.
Group I: .2M NH4Cl, .2M HCl, .2M C6H5NH3Cl, .2M (C2H5)3NHCl
Group II: .2M KOI, .2M NaCN, .2M KOCl, .2M NaNO2
a. The solution with the lowest pH
b. The solution with the highest pH
c. The solution with the pH closest to 7