A biochemist prepares two stocks of sodium phosphate buffer by titrating phosphoric acid with sodium hydroxide. She prepares a 0.10 M solution of sodium phosphate buffer at pH 7.20, and she prepares a 0.10 M solution of sodium phosphate buffer at pH 12.35. If she mixes 50. mL of the pH 7.20 buffer with 30. mL of the pH 12.35 buffer, what will be the pH of the resulting solution? The pKas of phosphoric acid are 2.15, 7.20, and 12.35.

A biochemist prepares two stocks of sodium phosphate buffer by titrating phosphoric acid with sodium hydroxide. She prepares a 0.10 M solution of sodium phosphate buffer at pH 7.20, and she prepares a 0.10 M solution of sodium phosphate buffer at pH 12.35. If she mixes 50. mL of the pH 7.20 buffer with 30. mL of the pH 12.35 buffer, what will be the pH of the resulting solution? The pKas of phosphoric acid are 2.15, 7.20, and 12.35.

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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