A 1.200-g sample of a mixture of NaOH (FW 40.00 g/mol) and NayCO3 (FW 105.99 g/mol) with inert impurity is dissolved in 100 mL water and titrated with 0.150 M HCI.With phenolphthalein as the indicator, a 50.00 mL aliquot of the solution turns colorless after the addition of 30.00 mL of the acid. Methyl orange is then added, and 7.00 ml more of the acid are required for the color to change to pink. What is the percentage of NaOH in the sample?

A 1.200-g sample of a mixture of NaOH (FW 40.00 g/mol) and NayCO3 (FW 105.99 g/mol) with inert impurity is dissolved in 100 mL water and titrated with 0.150 M HCI.With phenolphthalein as the indicator, a 50.00 mL aliquot of the solution turns colorless after the addition of 30.00 mL of the acid. Methyl orange is then added, and 7.00 ml more of the acid are required for the color to change to pink. What is the percentage of NaOH in the sample?

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 74QAP: Fifty cm3 of 1.000 M nitrous acid is titrated with 0.850 M NaOH. What is the pH of the solution (a)...

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