What is the pH of a 0.15 M hydrogen selenite ion, HSeO₃⁻, if its K_a and K_b values are 4.8×10⁻⁹ and 4.2×10⁻¹², respectively?

• A. 5.68
• B. 4.57
• C. 9.14
• D. 8.32

Answer: (B)