Reactions of Lead Ions (Pb²⁺) with Cloride ion

Soluble chlorides, such as hydrochloric acid, precipitate white lead chloride from Pb2+ solutions, when the solutions are not too dilute:

Lead chloride is a slightly soluble salt, with a solubility of 10 g/L at 20º. The solubility of PbCl₂

 increases very rapidly as the temperature rises. At 100º it has a solubility of 33.5 g/L. However, PbCl2 precipitates very slowly, particularly when other ions that form insoluble chlorides are not present. The precipitation can be speeded up by vigorously rubbing the inside of the test tube with a stirring rod. Even then the precipitate may not form until 3 to 5 minutes after mixing the solutions. PbCl₂

 dissolves in excess chloride ion as a result of the formation of the tetrachloroplumbate(II) complex ion: