Question

Rohan heard that instructions were given to the laboratory attendent to store a particular chemical i.e., keep it in the darkroom, add some urea in it, and keep it away from dust. This chemical acts as an oxidising as well as a reducing agent in both acidic and alkaline media. This chemical is important for use in the pollution control treatment of domestic and industrial effluents. Write the name of this compound. Explain why such precautions are taken for storing this chemical.

Answer 1

\[\ce{H2O2}\] is decomposed by light and dust particles. Urea is added as a negative catalyst, i.e., to check its decomposition.

\[\ce{2H2O2 (l) -> 2H2O (l) + O2 (g)}\]

Because of the oxidizing properties, \[\ce{H2O2}\] is widely used to control pollution by oxidation of harmful cyanides and obnoxious smelling sulphides present in domestic and industrial effluents. It also helps in sewage disposal by supplying \[\ce{O2}\] for oxidation of organic matter present – in sewage waters.