Final answer:
To calculate the Kp value for the solubility of Pb₃(PO₄)₂, convert the solubility to molar solubility, determine the concentrations of the ions, and apply the Ksp equation. The Kp value for the solubility of Pb₃(PO₄)₂ is 3.01 x 10⁻³⁴.
Step-by-step explanation:
To calculate the Kp value for the solubility of Pb₃(PO₄)₂, we need to first convert the solubility to molar solubility. The molar solubility is the concentration of the ions formed when the compound dissolves.
The dissociation equation for Pb₃(PO₄)₂ is: Pb₃(PO₄)₂(s) → 3Pb²⁺(aq) + 2PO₄³⁻(aq)
Given that the solubility of Pb₃(PO₄)₂ is 6.2 x 10^-12 mol/L, the concentration of Pb²⁺ ions is 3 times the solubility, and the concentration of PO₄³⁻ ions is 2 times the solubility.
Therefore, the molar solubility of Pb₃(PO₄)₂ is: Molar solubility = 3 * 6.2 x 10^-12 mol/L (for Pb²⁺)
= 1.86 x 10⁻¹¹ mol/L
Now, we can apply the Ksp equation for Pb₃(PO₄)₂: Ksp = [Pb²⁺]³[PO₄³⁻]²
Substituting the molar solubility values, we have:
Ksp = (1.86 x 10⁻¹¹ mol/L)³ * (1.86 x 10⁻¹¹ mol/L)²
= 3.01 x 10⁻³⁴
Therefore, the Kp value for the solubility of Pb₃(PO₄)₂ is 3.01 x 10⁻³⁴.