Vernon was asked to isolate a storage protein from Saba banana (Musa balbisiana Colla). According to the protocol given by his laboratory instructor, the storage protein must be stored in a 0.750 M citric acid buffer solution pH 6.21. Citric acid is a triprotic acid that follows a dissociation equilibrium shown below: H3C6H5O7 H₂C6H5O7 HC6H5O72- C6H50,³- Ka₂ 1.82 x 10-5 Ka, 8.32 x 10-4 Help him prepare the buffer by answering the following questions: 1. Based on the chemical equation above, which species will be the (a) acidic and (b) basic component of the buffer to be prepared? 2. Write the complete equilibrium reaction involved in the buffer system. 3. Write the pertinent chemical equations to illustrate what happens upon the addition of small amounts of (a) strong base and (b) strong acid to the buffer system. 4. Based on your answer in number 1, choose among the salts given in the table below and calculate the amounts of the components needed to prepare 500 mL of the buffer solution. Ka3 = 3.98 x 106 COMPOUND/SALT H3C6H5O7 NaH₂C6H5O7 Na₂HC6H5O7 Na3C6H5O7 MOLAR MASS, g/mol 192.124 214.106 236.088 258.070

Vernon was asked to isolate a storage protein from Saba banana (Musa balbisiana Colla). According to the protocol given by his laboratory instructor, the storage protein must be stored in a 0.750 M citric acid buffer solution pH 6.21. Citric acid is a triprotic acid that follows a dissociation equilibrium shown below: H3C6H5O7 H₂C6H5O7 HC6H5O72- C6H50,³- Ka₂ 1.82 x 10-5 Ka, 8.32 x 10-4 Help him prepare the buffer by answering the following questions: 1. Based on the chemical equation above, which species will be the (a) acidic and (b) basic component of the buffer to be prepared? 2. Write the complete equilibrium reaction involved in the buffer system. 3. Write the pertinent chemical equations to illustrate what happens upon the addition of small amounts of (a) strong base and (b) strong acid to the buffer system. 4. Based on your answer in number 1, choose among the salts given in the table below and calculate the amounts of the components needed to prepare 500 mL of the buffer solution. Ka3 = 3.98 x 106 COMPOUND/SALT H3C6H5O7 NaH₂C6H5O7 Na₂HC6H5O7 Na3C6H5O7 MOLAR MASS, g/mol 192.124 214.106 236.088 258.070

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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