Question

A mixture is prepared using 27.00 mL of a 0.0786 M weak base (pKa 4.635), 27.00 mL of a 0.0590 M w Map acid (pKa 3.252) and 1.00 mL of 0.000105 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 0.1063. The molar absorptivity (E) values for HIn and its deprotonated form In at 550 nm are 2.26 x104 Mcmand 1.53x104 M-cm1 respectively. What is the pH of the solution? Number What are the concentrations of In and Hln? Number [In ]= Number What is the pKa for HIn? Number pKa

Answer 1

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key 0.021-a) (o.ot 17.χ 2 o. 00119-0. D082 NA 3.2% t O.0082 半

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