Strong base is dissolved in 715 mL of 0.400 M weak acid (K, = 4.75 x 10-5) to make a buffer with a pH of 4.11. Assume that the volume remains constant when the base is added. HA(aq) + OH (aq) → H, O(1) + A-(aq) Calculate the pKa value of the acid, and determine the number of moles of acid initially present. pKa initial amount: mol HA When the reaction is complete, what is the concentration [A] ratio of conjugate base to acid? [HA] How many moles of strong base were initially added? amount added: mol OH-

Strong base is dissolved in 715 mL of 0.400 M weak acid (K, = 4.75 x 10-5) to make a buffer with a pH of 4.11. Assume that the volume remains constant when the base is added. HA(aq) + OH (aq) → H, O(1) + A-(aq) Calculate the pKa value of the acid, and determine the number of moles of acid initially present. pKa initial amount: mol HA When the reaction is complete, what is the concentration [A] ratio of conjugate base to acid? [HA] How many moles of strong base were initially added? amount added: mol OH-

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter15: Equilibria Of Other Reaction Classes

Section: Chapter Questions

Problem 82E: The simplest amino acid is glycine, H2NCH2CO2H. The common feature of amino acids is that they...

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