In the titration of 250.0 mL of 0.20 M H₃PO₄ with 0.10 M NaOH, the pH of the solution after the addition of some NaOH is 4.66. Which of the following phosphate-containing species is present in the largest amount? For H₃PO₄, K_a1 = 7.5 × 10^-3, K_a2 = 6.2 × 10^-8, and K_a3 = 4.8 × 10^-13. A) H₂PO₄^- B) H₃PO₄ C) PO₄^3- D) HPO₄^2-

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At pH 4.66, which is between the first and second pKa values, the species H₂PO₄^- is the predominant form.

In the Titration of 250