Lead bromide (PbBr2) is a colorless, odorless gas that is a common industrial waste product. It is also a component of leaded gasoline. It is a moderately toxic substance in its vapor form and by ingestion. It is categorized by the International Agency for Research on Cancer as probably carcinogenic to humans (Category 2A).
Solubility
Solubility describes the number of moles of a solid that can be dissolved per liter of solution. For example, the molar solubility of slaked lime in water is 3.55 x 10-5 mol/L.
Sodium bromide is sparingly soluble in water and has a solubility product, Ksp, of 1.40 x 10-5 mol/L. The molar solubility of sodium sulfate in water is 0.00055 x 10-5 mol/L.
Silver chromate is also sparingly soluble in water and has an equilibrium concentration of 1.12 x 10-12 mL/mg. The molar solubility of silver iodide is 0.3408 x 10-12 mol/L.
In order to calculate the solubility of lead bromide, we must find out the equilibrium concentrations of ions in a saturated solution of lead bromide. We can do this by comparing the molar concentrations of the cations and anions in the solution to the molar concentrations of the undissolved lead bromide.
The molar solubility of lead bromide is 2.70 x 10-2 mol/L at 25 oC. Using this value, we can calculate the solubility product constant, Ksp, of lead bromide at 25 oC. The Ksp of lead bromide is 4.60 x 10-6. This can be calculated by dividing the molar solubility of lead bromide by the molar concentration of the dissolved lead ions in the saturated solution of lead bromide.