A weak acid (HA) can be used to make a buffer for biochemical experiments: HA=H++Aa. Calculate the pH of a solution made by adding 0.060 moles of HA to 250mLs of de-ionized water. 4 2 = 0.01mal 0.250 ** ** o 0.24M HA=H" +A" ka. 10 phe = 10 46 = 5.47 × 105 3.47 × 10°5 = X -x 5.47 × 105 (024-x) = x² 8.33×108 0.24 b. Now suppose 0.020 moles of strong acid (NaOH) is added to the solution from part a. Calculate the new pH (you may -4 ignore dilution). moles of 4 = 2.9 × 10 *0.25 = 7.25 × 10* M HA + NaOH - NaA+H2O moles

A weak acid (HA) can be used to make a buffer for biochemical experiments: HA=H++Aa. Calculate the pH of a solution made by adding 0.060 moles of HA to 250mLs of de-ionized water. 4 2 = 0.01mal 0.250 o 0.24M HA=H" +A" ka. 10 phe = 10 46 = 5.47 × 105 3.47 × 10°5 = X -x 5.47 × 105 (024-x) = x² 8.33×108 0.24 b. Now suppose 0.020 moles of strong acid (NaOH) is added to the solution from part a. Calculate the new pH (you may -4 ignore dilution). moles of 4 = 2.9 × 10 0.25 = 7.25 × 10 M HA + NaOH - NaA+H2O moles

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter15: Acid-base Equilibria

Section: Chapter Questions

Problem 8ALQ: You have a solution of the weak acid HA and add some of the salt NaA to it. What are the major...

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