1. According to Table 27.4, if you mix 45.0 mL of a 0.1 M NaH₂PO4 solution with 55.0 mL of a 0.1 M NazHPO4 solution, you will create a buffer with a pH of 6.9.¹ Using the Henderson-Hasselback equation, determine if this pH is based on the concentration ratio of the base/acid or the activity ratio of the base/acid. Show your work to prove your answer. Ionic Strength (µ) 0.001 0.005 0.01 0.05 0.1 0.2 Activity Coefficient for H₂PO4 Activity Coefficient for HPO4²- 0.964 0.867 0.928 0.740 0.902 0.660 0.820 0.445 0.775 0.335 0.750 0.290

1. According to Table 27.4, if you mix 45.0 mL of a 0.1 M NaH₂PO4 solution with 55.0 mL of a 0.1 M NazHPO4 solution, you will create a buffer with a pH of 6.9.¹ Using the Henderson-Hasselback equation, determine if this pH is based on the concentration ratio of the base/acid or the activity ratio of the base/acid. Show your work to prove your answer. Ionic Strength (µ) 0.001 0.005 0.01 0.05 0.1 0.2 Activity Coefficient for H₂PO4 Activity Coefficient for HPO4²- 0.964 0.867 0.928 0.740 0.902 0.660 0.820 0.445 0.775 0.335 0.750 0.290

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter15: Additional Aqueous Equilibria

Section: Chapter Questions

Problem 93QRT: When 40.00 mL of a weak monoprotic acid solution is titrated with 0.100-M NaOH, the equivalence...

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