A 100.0 mL sample of 0.10 mol L^-1 NH₃ is titrated with 0.10 mol L^-1 HNO₃. Determine the pH of the solution before the addition of any HNO₃. The K_b of NH₃ is 1.8 × 10^-5. A) 4.74 B) 9.26 C) 11.13 D) 13.00 E) 12.55

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Quizplus · Accepted Answer

The pH of the solution can be calculated using the formula for the pH of a weak base: pH = 14 - pOH. First, calculate the pOH using the formula: pOH = -log(√(Kb × [NH3])). Substituting the given values, pOH = -log(√(1.8 × 10^-5 × 0.10)) = 2.87. Therefore, pH = 14 - 2.87 = 11.13.

A 1000 ML Sample of 0