Discuss the preparation of ozone by Sieman's Ozoniser.

Explanation

Preparation of Ozone : When silent electric discharge is passed through dried oxygen or air in an apparatus called ozoniser, it is partially converted into ozone. The product obtained in the gaseous form contains 10-15% ozone. Since the conversion of dioxgyen on ozone is an endothermic process, therefore, ozone is unstable.
`3O_2 overset("Silent Electric discharge")hArr 2O_3 , DeltaH =+ 258 KJ`
Due to thermal decomposition of ozone the yield of ozone when produced by passing oxygen over electric spark is much less.
Siemen ozoniser consists of two co-axial tubes fused at one end. The inner side of the outer tube and outer side of the inner tube are coated with tin foils and are connected to the two terminals of an induction coil. One end of the co-axial tube end has an outlet for ozonised oxygen. A show current of dry and cold dioxygen is passed through the the inlet into the tube and silent electric discharge is. passed. 10-15% of dioxygen gets converted to ozone and is taken out from the outlet.