Question

Give an example each of the following types of double displacement reaction:

When a precipitate is formed.

Answer 1

1. Double displacement reaction

A double displacement reaction is a chemical reaction displayed between two compounds. There is a displacement of positive and negative ions of these two compounds to form new compounds.

2. Example of displacement reaction

$$\begin{gathered} \mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{aq}\right)+2\mathrm{KI}\left(\mathrm{aq}\right)\to 2{\mathrm{KNO}}_3\left(\mathrm{aq}\right)+{\mathrm{PbI}}_2\left(\mathrm{s}\right) \\ \mathrm{Lead}\mathrm{nitrate}\mathrm{Potassium}\mathrm{Potassium}\mathrm{Lead}\mathrm{iodide} \\ \mathrm{iodide}\mathrm{nitrate} \end{gathered}$$

This double displacement reaction occurs between Lead nitrate and Potassium iodide to form Potassium nitrate. The insoluble precipitate is called Lead iodide.