Answer:
Qsp = 3.36x10⁻⁸
Explanation:
The Ksp of calcium fluoride is defined as:
CaF₂(s) → Ca²⁺(aq) + 2F⁻(aq)
Ksp = 3.9x10⁻¹¹ = [Ca²⁺] [F⁻]²
Where concentrations of ions are in equilibrium.
Molarity of Ca²⁺ and F⁻ is:
[Ca²⁺] = 0.1250L × (0.00615mol / L) = 7.688x10⁻⁴mol / 0.4550L = 1.690x10⁻³M
[F⁻] = 0.3300L × (0.00615mol / L) = 2.030x10⁻³mol / 0.4550L = 4.460x10⁻³M
Thus, Qsp is:
Qsp = 1.690x10⁻³M × (4.460x10⁻³M)²
Qsp = 3.36x10⁻⁸