Question

Is $PbC{l_2}$ soluble in water?

Answer 1

Lead chloride $\left( {PbC{l_2}} \right)$ is a white solid. It is an inorganic compound which is the most widely used lead based reagent in many reactions. It is also known as Plumbous chloride. Exposure of lead chloride may cause lead poisoning.

Complete answer:
Lead chloride $\left( {PbC{l_2}} \right)$ is not soluble in cold water. Only a small amount may get dissolved (sparingly soluble) in cold water. But in hot water lead chloride dissolves to give a colourless solution. The solubility product $\left( {{K_{sp}}} \right)$ of lead chloride was found to be $1.7 \times {10^{ - 5}}$ at ${20^o}C$ .
The chlorides, bromides and iodides of all the metals except lead, silver and mercury $\left( I \right)$ are soluble in water. $PbC{l_2},PbB{r_2},Pb{I_2}$ are soluble in hot water.
Thus, we found that $PbC{l_2}$ is not soluble in cold water but it is soluble in hot water.
Lead chloride is insoluble in cold water but it has been found that the addition of $HCl$ increases the solubility due to the formation of soluble complex anions like $PbC{l_3}^ -$ . The added chloride ion $\left( {C{l^ - }} \right)$ breaks the chloride bridges that constitutes the polymeric framework of solid $\left( {PbC{l_2}} \right)$
$PbC{l_2} + C{l^ - }\left( {aq} \right) \to PbC{l_3}^ - \left( {aq} \right)$ .

Additional Information:
Lead chloride $\left( {PbC{l_2}} \right)$ naturally occurs in the form of mineral cotunnite. It is used in the production of infrared transmitting glass and ornamental glass called aurene glass. Another important application of lead chloride is that it is used in the synthesis of barium lead titanate ceramics.

Note:
We have seen that lead chloride is not soluble in cold water or sparingly soluble but it is completely soluble in hot water. A basic chloride of lead is used as pigment in white paint but lead paints are now banned due to health hazards.