Question

(a)How is ozonized oxygen prepared in the laboratory ? give reason.
(b) Give the composition of “oleum”.

Answer 1

A. By passing a slow dry steam of oxygen through a silent electrical discharge, oxygen can be converted to ozone. The product formed through this process is known as ozonized oxygen.
B. Oleum is fuming sulfuric acid. It is the solution of the various compositions of sulfur trioxide in sulfuric acid.

Complete step by step answer:
A. Ozone is basically referred to as ozonized oxygen. The function of ozone is that it prevents the living would from harmful radiations (UV) coming from the sun. It lies generally fifteen miles above earth’s surface.
Ozone is prepared in the laboratory by passing silent electric discharge through dry oxygen. Silent electric discharge is given in order to produce less heat as ozone is prone to decompose back into oxygen with increase in temperature. What happens by electric discharge is that some of the oxygen molecules dissociate and then atomic oxygen combines with oxygen molecules to form ozone.
The reaction equations are :
${O_2}\xrightarrow{{energy}}O + O$
${O_2} + O \to {O_3}$
$3{O_2} \rightleftharpoons 2{O_3} - {\text{ energy}}$ .
The mixture that is obtained generally contains $5 - 10\%$ ozone by volume and it is known as ozonized oxygen.
B. Oleum, also known as fuming sulfuric acid is a solution of compositions of sulfur trioxide in sulfuric acid or may be sometimes disulfuric acid.
Formula of oleum is ${H_2}{S_2}{O_7}$ .
Reaction equation can be writer is :
${H_2}S{O_4} + S{O_3} \to {H_2}{S_2}{O_7}$ .

Note: A. The apparatus that is used for the preparation of ozonized oxygen is known as ozonizer. Two types of ozonizers are specially used, that are The Seimen’s and Brodie ozonizers.
B. Oleum is a fuming liquid, it might release toxic fumes. Moreover, it is an important intermediate in the manufacture of sulfuric acid.