An alkaline sample of sodium compounds weighing 1.196 g was dissolved in water, cooled at 15 deg C, treated with 2 drops of phenolphthalein indicator and titrated with 1.058 N H2SO4 requiring 6.8 mL to render the solution colorless. Upon adding 2 drops of methyl orange and continuing the titration 16.5 mL more of the acid was needed to complete analysis. What is the quantitative composition of the sample?

An alkaline sample of sodium compounds weighing 1.196 g was dissolved in water, cooled at 15 deg C, treated with 2 drops of phenolphthalein indicator and titrated with 1.058 N H2SO4 requiring 6.8 mL to render the solution colorless. Upon adding 2 drops of methyl orange and continuing the titration 16.5 mL more of the acid was needed to complete analysis. What is the quantitative composition of the sample?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter13: Titrations In Analytical Chemistry

Section: Chapter Questions

Problem 13.5QAP

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An alkaline sample of sodium compounds weighing 1.196 g was dissolved in water, cooled to 15°C, treated with 2 drops of Pp indicator and titrated with 1.058 N H2SO4 requiring 6.8 ml to render the solution colorless. Upon adding 2 drops of MO and continuing the titration, 16.5 ml more of the acid were needed to complete the analysis. What is the quantitative composition of the sample? MW: NaOH = 40.0, Na2CO3 = 106.0, NaHCO3 = 84.01
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