The Ksp (solubility product constant) of lead(II) hydroxide, Pb(OH)2, is 1.43 x 10⁻²⁰.
While the original question referred to 'pboh2', this is commonly understood as a typographical representation of lead(II) hydroxide, which has the chemical formula Pb(OH)2.
Understanding the Ksp of Lead(II) Hydroxide
The solubility product constant (Ksp) is a measure of the solubility of an ionic compound in water. For sparingly soluble ionic compounds like lead(II) hydroxide, Ksp represents the equilibrium between the undissolved solid and its ions in a saturated solution. A very small Ksp value, such as that for Pb(OH)2, indicates that the compound has very low solubility in water.
Dissolution Equilibrium of Pb(OH)2
When lead(II) hydroxide dissolves in water, it dissociates into its constituent ions, lead(II) ions (Pb²⁺) and hydroxide ions (OH⁻), according to the following equilibrium reaction:
Pb(OH)2(s) ⇌ Pb²⁺(aq) + 2OH⁻(aq)
Ksp Expression
The Ksp expression for lead(II) hydroxide is written as the product of the concentrations of its dissolved ions, each raised to the power of their stoichiometric coefficients from the balanced dissolution equation:
Ksp = [Pb²⁺][OH⁻]²
Where:
[Pb²⁺]is the molar concentration of lead(II) ions in a saturated solution.[OH⁻]is the molar concentration of hydroxide ions in a saturated solution.
Key Data for Lead(II) Hydroxide
| Compound | Chemical Formula | Ksp Value |
|---|---|---|
| Lead(II) Hydroxide | Pb(OH)2 | 1.43 x 10⁻²⁰ |
This extremely small Ksp value confirms that lead(II) hydroxide is a highly insoluble compound. Its limited solubility is an important factor in environmental chemistry, especially concerning lead contamination and remediation strategies, as the concentration of dissolved lead ions in water will remain very low.
