A 3.50g sample of histidine dihydrochloride (fw 228.08g/mol) in water and diluting to a final volume of 50.00ml. The resulting solution is then titrate with 0.500M NaOH. calculate the pH at each of the following points
a) initial
b) each equivalence point
c) 10.00ml before each equivalence point
d) 20ml after last equivalent point