We dissolve 3.54 g of an unknown acid, HA, in enough water to produce 25.0 mL of solution. We titrate this solution with a 0.250 M solution of NaOH. It takes 20.7 mL of the NaOH solution to reach the equivalence point. The pH at the equivalence point is 12.00. (a) What is the molar mass of HA? (b) What is the pKa value of HA(aq)? (c) What was the original pH of the solution of HA(aq)?

We dissolve 3.54 g of an unknown acid, HA, in enough water to produce 25.0 mL of solution. We titrate this solution with a 0.250 M solution of NaOH. It takes 20.7 mL of the NaOH solution to reach the equivalence point. The pH at the equivalence point is 12.00. (a) What is the molar mass of HA? (b) What is the pKa value of HA(aq)? (c) What was the original pH of the solution of HA(aq)?

Chemistry & Chemical Reactivity

10th Edition

ISBN:9781337399074

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

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

Chapter18: Principles Of Chemical Reactivity: Entropy And Free Energy

Section: Chapter Questions

Problem 44PS

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