A 0.717 gram sample of an unknown monoprotic acid is dissolved in 40.0 mL of water and titrated with a a 0.221 M aqueous barium hydroxide solution. It is observed that after 8.28 milliliters of barium hydroxide have been added, the pH is 3.465 and that an additional 4.32 mL of the barium hydroxide solution is required to reach the equivalence point. (1) What is the molecular weight of the acid? g/mol (2) What is the value of Ka for the acid?

A 0.717 gram sample of an unknown monoprotic acid is dissolved in 40.0 mL of water and titrated with a a 0.221 M aqueous barium hydroxide solution. It is observed that after 8.28 milliliters of barium hydroxide have been added, the pH is 3.465 and that an additional 4.32 mL of the barium hydroxide solution is required to reach the equivalence point. (1) What is the molecular weight of the acid? g/mol (2) What is the value of Ka for the acid?

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter15: Acid–base Equilibria

Section: Chapter Questions

Problem 57P

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