An acid-base indicator, hln, dissociates according to the following reaction in an aqueous solution. hinlag) in (aq) h (aq) the protonated form of the indicator, hln, has a molar absorptivity of 2929 m cm 1 and the deprotonated form, in has a molar absorptivity of 20060 m-1. cm 1 at 440 nm. the ph of a solution containing a mixture of hin and in s adjusted to 6.12. the total concentration of hin and in s 0.000127 m. the absorbance of this solution was measured at 440 nm in a 1.00 cm cuvette and was determined to be 0.818. calculate pka for hin.