1. A weak acid has an initial pH of 3.460 when it is dissolved in 100.0 mL of water and a pH of 3.960 at the midpoint in the titration. a. Calculate the acid dissociation constant, Ka, for this acid. b. If exactly 40.00 mL of 0.1000 M NaOH is required to reach the equivalence point when the same unknown acid as in Question la is dissolved in 100.0 mL of water, what is the concentration of the salt (NaA) formed? c. Determine the pH at the equivalence point for the same unknown acid.

1. A weak acid has an initial pH of 3.460 when it is dissolved in 100.0 mL of water and a pH of 3.960 at the midpoint in the titration. a. Calculate the acid dissociation constant, Ka, for this acid. b. If exactly 40.00 mL of 0.1000 M NaOH is required to reach the equivalence point when the same unknown acid as in Question la is dissolved in 100.0 mL of water, what is the concentration of the salt (NaA) formed? c. Determine the pH at the equivalence point for the same unknown acid.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter15: Additional Aqueous Equilibria

Section: Chapter Questions

Problem 44QRT

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