Oxalic acid,H₂C₂O₄ has acid dissociation constants K_a1 = 5.9 × 10^-2 and K_a2 = 6.4 × 10^-5.What is the pH after 20.00 mL of 0.0500 M NaOH is added to 5.00 mL of 0.2000 M H₂C₂O₄? A)1.23 B)2.10 C)2.80 D)4.19

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Quizplus · Accepted Answer

After adding NaOH, the solution is a buffer system of HC2O4^- and C2O4^2-. Using the Henderson-Hasselbalch equation with pKa2, the pH is approximately 2.80.

Oxalic Acid,H2C2O4 Has Acid Dissociation Constants Ka1 = 5

Oxalic Acid,H₂C₂O₄ Has Acid Dissociation Constants K_a1 = 5