Question

6. Write one of the reaction for each of the following characteristics :

(d) Formation of percipitate

Answer 1

Part 1: Chemical Reaction

• A chemical reaction may take place when two or more reactants come in contact with one another resulting in the formation of new substances called products accompanied by the transfer of energy among them.

Part 2: Formation of Precipitate

• Certain chemical reactions are characterised by the formation of precipitate ( an insoluble substance ), when the solutions of the soluble chemical compounds are mixed together. The following example will prove the point.
• Potassium iodide solution (colorless) reacts with lead acetate solution (colourless) to form potassium acetate solution and yellow precipitate of lead iodide.
• $\underset{\mathrm{Potassium}\mathrm{Iodide}}{2\mathrm{KI}\left(\mathrm{s}\right)}+\underset{\mathrm{Lead}\mathrm{acetate}}{{\left({\mathrm{CH}}_3\mathrm{COO}\right)}_2\left(\mathrm{s}\right)}\to \underset{\mathrm{Potassium}\mathrm{Acetate}}{2{\mathrm{CH}}_3\mathrm{COOK}\left(\mathrm{s}\right)}+\underset{\underset{(\mathrm{Yellow}\mathrm{precipitate})}{\mathrm{Lead}\mathrm{Iodide}}}{{\mathrm{PbI}}_2\left(\mathrm{s}\right)}$