Question

Calculate the p value of each ion indicated:
Ba2+, Mn2+, Cl- in a solution of BaCl2 7.65x10-3 M and MnCl2 1.54 M

Answer 1

27/208  = normality

12 x 10^-2 approx  = normality

nw Ka = 14.3 x 10^-3

pKa = 3 - log 14

now, after getting the pKa put it in formula  :
pH = pKa + log concn of ion/concn of salt and you'll get it

hope this helps