Question

Write one of the reaction for each of the following characteristics

change of colour

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: Reaction in which change in color takes place:

• Certain chemical reactions are characterized by a change in colour of reacting substancs.
• For example, When red lead oxide is heated strongly, it forms yellow coloured lead monoxide and gives off oxygen gas.
• $\underset{\mathrm{Red}\mathrm{lead}\mathrm{oxide}\mathrm{Lead}\mathrm{monoxide}\mathrm{Oxygen}}{2{\mathrm{Pb}}_3{\mathrm{O}}_4(\mathrm{red}\mathrm{colour})\stackrel{\mathrm{heat}}{\to }6\mathrm{PbO}(\mathrm{yellow}\mathrm{colour})+{\mathrm{O}}_2}$