Strong base is dissolved in 715 mL of 0.600 M weak acid (K₁ = 4.12 × 10-5) to make a buffer with a pH of 4.09. Assume that the volume remains constant when the base is added. HA(aq) + OH¯(aq) + H,O(l) + A-(aq) Calculate the pKą value of the acid, and determine the number of moles of acid initially present. pKa = initial amount: When the reaction is complete, what is the concentration ratio of conjugate base to acid? [A-] [HA] = How many moles of strong base were initially added? amount added: mol HA mol OH-

Strong base is dissolved in 715 mL of 0.600 M weak acid (K₁ = 4.12 × 10-5) to make a buffer with a pH of 4.09. Assume that the volume remains constant when the base is added. HA(aq) + OH¯(aq) + H,O(l) + A-(aq) Calculate the pKą value of the acid, and determine the number of moles of acid initially present. pKa = initial amount: When the reaction is complete, what is the concentration ratio of conjugate base to acid? [A-] [HA] = How many moles of strong base were initially added? amount added: mol HA mol OH-

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

Chapter17: Principles Of Chemical Reactivity: Other Aspects Of Aqueous Equilibria

Section: Chapter Questions

Problem 116SCQ: Two acids, each approximately 0.01 M in concentration, are titrated separately with a strong base....

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