A mixture is prepared using 27.00 mL of a 0.0729 M weak base (pka=4.623) , 27.00 mL of a 0.0532 M weak acid (pka=3.268) and 1.00 mL of 1.22×10^−4 M HIn and then diluting to 100.0 mL, where HIn is the protonated indicator. The absorbance measured at 550 nm in a 5.000 cm cell was 0.1289 . The molar absorptivity values for HIn and its deprotonated form In− at 550 nm are 2.26×10^4 M^−1cm^−1 and 1.53×10^4 M^−1cm^−1 , respectively. (a)- What is the pH of the solution?

(b)- What are the concentration of ln- and Hln?

(c)- What is pKa for Hln?