What is the pH of an aqueous solution labeled "0.50 M sodium fluoride" if the ionization constant of hydrofluoric acid is 6.0 × 10^-4? A)10.8 B)8.5 C)7.1 D)6.9 E)5.5

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Quizplus · Accepted Answer

Sodium fluoride (NaF) dissociates in water to form Na+ and F-. The F- ion can react with water to form HF and OH-, making the solution basic. Using the ionization constant of HF (Ka = 6.0 × 10^-4), we can find the Kb for F- using the relation Kw = Ka * Kb, where Kw = 1.0 × 10^-14. Solving for Kb and using the concentration of F- (0.50 M), we can calculate the pOH and then the pH, which is approximately 8.5.

What Is the PH of an Aqueous Solution Labeled "0