We dissolve 2.77 g of an unknown acid, HA, in enough water to produce 25.0 mL of solution. The pH of this solution of HA(aq) is 1.33. We titrate this solution with a 0.250 M solution of NaOH. It takes 41.8 mL of the NaOH solution to reach the equivalence point. (a) What is the molar mass of HA? (b) What is the pKa value of HA(aq)? (c) What is the pH at the equivalence point? (d) What is the pH one third along the titration when you still have twice as much HA(aq) as A-(aq)?

We dissolve 2.77 g of an unknown acid, HA, in enough water to produce 25.0 mL of solution. The pH of this solution of HA(aq) is 1.33. We titrate this solution with a 0.250 M solution of NaOH. It takes 41.8 mL of the NaOH solution to reach the equivalence point. (a) What is the molar mass of HA? (b) What is the pKa value of HA(aq)? (c) What is the pH at the equivalence point? (d) What is the pH one third along the titration when you still have twice as much HA(aq) as A-(aq)?

Chemistry & Chemical Reactivity

9th Edition

ISBN:9781133949640

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter16: Principles Of Chemical Reactivity: The Chemistry Of Acids And Bases

Section: Chapter Questions

Problem 106GQ: The hydrogen phthalate ion, C8HsO4, is a weak acid with Ka = 3.91 106....

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