Lead chloride, solubility product constant

Calculate the solubility-product constant, Ksp, of lead(II) chloride, PbCl2, which has a solubility of 1.00 g/100.0 g H2O at a temperature other than 25 °C. 

In the calculation of the molar solubility of a compound such as leadfll) chloride, PbCb, given its solubility produet constant, the concentration of the ehloride ion. Cl", is exactly twice the concentration of the lead(II) ion, Pb. In the solubility product constant expression, this doubled concentration is also squared. However, when lead(II) chloride is precipitated by the combining of solutions of lead(II) nitrate, Pb(N03)2, and potassium chloride, KCl, the concentration of the chloride ion is not doubled before it is squared. Explain this difference. 

This equation is the equilibrium expression Avhich holds for all solutions that are saturated with lead chloride. We see that the product of the concentration of the lead ion and the square of the concentration of the chloride ion is equal to a constant, This constant (which has a constant value at a given temperature, but in general will change somewhat with the temperature) is called the solubility product of lead chloride. The solubility-product equation may be used to calculate the solubility oi lead chloride in solutions containing extra lead ions or extra ebibride ions. 

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