A 1.00 L buffer solution is 0.250 M in HF and 0.250 M in NaF.Calculate the pH of the solution after the addition of 100.0 mL of 1.00 M HCl.The K_a for HF is 3.5 × 10^-4. A) 3.09 B) 4.11 C) 3.82 D) 3.46 E) 2.78

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Quizplus · Accepted Answer

The correct answer is A because the pH of the solution after the addition of 100.0 mL of 1.00 M HCl can be calculated using the Henderson-Hasselbalch equation:pH = pKa + log([A-]/[HA])where pKa is the dissociation constant of the acid, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the acid.In this case, the pKa of HF is 3.5 × 10^-4, the concentration of the conjugate base (NaF) is 0.250 M, and the concentration of the acid (HF) is 0.250 M.Substituting these values into the Henderson-Hasselbalch equation, we get:pH = 3.5 × 10^-4 + log(0.250/0.250) = 3.5 × 10^-4Therefore, the pH of the solution after the addition of 100.0 mL of 1.00 M HCl is 3.5 × 10^-4.

A 100 L Buffer Solution Is 0