4. Use a 100-mL beaker to make 50 ml of sodium phosphate solution by mixing 0.8 mL of 2 M monobasic NaH,PO4, 4.2 ml of 2 M dibasic Na>HPO4, and 45 ml of H20 as shown in the table. Measure and record the pH. Pipette 20mL of this buffer solution and place it in a new 50-mL beaker. Add 1 ml of 1 M HCI or 1 M NaOH to each separate beaker and mix well. Measure and record the pH. Table 4: Buffered solution (phosphate) Calculated pH Measured pH 0.8 ml of 2 M monobasic NaH;PO, + 4.2 ml 7.66 of 2 M dibasic Na>HPOA +45 mL H2O 25 ml above mix buffer + 1 mL 1.0 M HCI 7.08 25 mL above mix buffer +1 mL 1.0 M NaOH 7.71 * The pKaz and pKas of phosphate groups are 6.8 and 12.3, respectively.

4. Use a 100-mL beaker to make 50 ml of sodium phosphate solution by mixing 0.8 mL of 2 M monobasic NaH,PO4, 4.2 ml of 2 M dibasic Na>HPO4, and 45 ml of H20 as shown in the table. Measure and record the pH. Pipette 20mL of this buffer solution and place it in a new 50-mL beaker. Add 1 ml of 1 M HCI or 1 M NaOH to each separate beaker and mix well. Measure and record the pH. Table 4: Buffered solution (phosphate) Calculated pH Measured pH 0.8 ml of 2 M monobasic NaH;PO, + 4.2 ml 7.66 of 2 M dibasic Na>HPOA +45 mL H2O 25 ml above mix buffer + 1 mL 1.0 M HCI 7.08 25 mL above mix buffer +1 mL 1.0 M NaOH 7.71 * The pKaz and pKas of phosphate groups are 6.8 and 12.3, respectively.

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter14: Acid- Base Equilibria

Section: Chapter Questions

Problem 97AE: A student intends to titrate a solution of a weak monoprotic acid with a sodium hydroxide solution...

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