Which is the best acid to use in the preparation of a buffer with pH = 3.3? A)HOI (K_a = 2.0 × 10^-11) B)HNO₂ (K_a = 4.5 × 10^-4) C)HNO₃ D)HIO₃ (K_a = 1.7 × 10^-1)

Question

Quizplus · Accepted Answer

The best acid for preparing a buffer with a pH close to 3.3 is the one whose pKa is closest to the desired pH. The pKa is the negative logarithm of the acid dissociation constant (Ka). For option B, HNO2 (Ka = 4.5 × 10^-4), the pKa is approximately 3.35, which is closest to the desired pH of 3.3.

Which Is the Best Acid to Use in the Preparation