A solution of NaF is added dropwise to a solution that is 0.0144 M in Ba²⁺. When the concentration of F^-exceeds M, BaF₂will precipitate. Neglect volume changes. For BaF₂, K_sp= 1.7 × 10^-⁶. A) 1.1 × 10^-² B) 1.2 × 10^-⁴ C) 2.4 × 10^-⁸ D) 2.7 × 10^-³ E) 5.9 × 10^-⁵

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Quizplus · Accepted Answer

To find the concentration of F⁻ needed to precipitate BaF₂, use the Ksp expression: Ksp = [Ba²⁺][F⁻]². Given Ksp = 1.7 × 10⁻⁶ and [Ba²⁺] = 0.0144 M, solve for [F⁻]: 1.7 × 10⁻⁶ = 0.0144 × [F⁻]². [F⁻]² = 1.7 × 10⁻⁶ / 0.0144, [F⁻] = √(1.7 × 10⁻⁶ / 0.0144) ≈ 0.011 M or 1.1 × 10⁻² M.

A Solution of NaF Is Added Dropwise to a Solution