試題詳解

9. Consider the titration of 100.0 mL of a 0.05 M solution of the hypothetical weak acid H₃X (Ka₁=1.0x10^-3, Ka₂=1.0x10^-7, Ka₃=1.0x10^-12) with 0.100 М КОН. Calculate the pH of the solution after adding 25.0 mL KOH.
(A) 2.2
(B) 2.8
(C) 3.0
(D) 3.9
(E) 4.5