A sample may contain NaOH, NazCO3 and NaHCO3, alone or in some combination, along with inert material. A sample with a mass of 857.6 mgwas dissolved and titrated w ith0.1163 M HCI. The volume of HCl used from 0 to methylred endpoint (Phenolphthalein endpoint was not monitored here) was found to be 36.54 mL. Another 228.8 mg portion of the sample was titrated to the phenolphthalein endpoint and 10.82 mL was used up for this titration. a. What is the composition of the sample? b. Calculate the percentage of each of the component present.

A sample may contain NaOH, NazCO3 and NaHCO3, alone or in some combination, along with inert material. A sample with a mass of 857.6 mgwas dissolved and titrated w ith0.1163 M HCI. The volume of HCl used from 0 to methylred endpoint (Phenolphthalein endpoint was not monitored here) was found to be 36.54 mL. Another 228.8 mg portion of the sample was titrated to the phenolphthalein endpoint and 10.82 mL was used up for this titration. a. What is the composition of the sample? b. Calculate the percentage of each of the component present.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter21: Potentiometry

Section: Chapter Questions

Problem 21.22QAP

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