Which is the best acid to use in the preparation of a buffer with pH = 9.3? A)CH₃NH₂ (K_b = 3.7 × 10^-4) B)NH₃ (K_b = 1.8 × 10^-5) C)NH₂OH (K_b = 9.1 × 10^-9) D)C₆H₅NH₂ (K_b = 4.3 × 10^-10)

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Quizplus · Accepted Answer

To prepare a buffer with pH = 9.3, we need a weak base with a pKa close to 9.3. The pKa can be found using pKa = 14 - pKb. For NH3, pKb = 4.74, so pKa = 9.26, which is closest to 9.3.

Which Is the Best Acid to Use in the Preparation