A mixed aqueous solution of HCl and sulfurous acid (H₂SO3; Ka1 = 1.39x10-2; Ka2 = 6.73x10-8) is titrated with 0.1000-M NaOH. The first end point (ethyl orange indicator) is reached after 38.91 mL of NaOH has been added. The second end point (thymolphthalein indicator) is reached after a total of 54.79 mL of NaOH has been added. What quantity of HCI (units of mol or mmol) was present in the initial mixture? 2.303 mol Submit Answer Incorrect. Tries 2/5 Previous Tries What quantity of sulfurous acid (units of mol or mmol) was present in the initial mixture? 1.59 mol

A mixed aqueous solution of HCl and sulfurous acid (H₂SO3; Ka1 = 1.39x10-2; Ka2 = 6.73x10-8) is titrated with 0.1000-M NaOH. The first end point (ethyl orange indicator) is reached after 38.91 mL of NaOH has been added. The second end point (thymolphthalein indicator) is reached after a total of 54.79 mL of NaOH has been added. What quantity of HCI (units of mol or mmol) was present in the initial mixture? 2.303 mol Submit Answer Incorrect. Tries 2/5 Previous Tries What quantity of sulfurous acid (units of mol or mmol) was present in the initial mixture? 1.59 mol

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter14: Equilibria In Acid-base Solutions

Section: Chapter Questions

Problem 37QAP: Given three acid-base indicatorsâ€”methyl orange (end point at pH 4), bromthymol blue (end point at...

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