Question

Ozone is tested by:
A. $Ag$
B. $Hg$
C. $Zn$
D. $Au$

Answer 1

We know that Ozone is an allotrope of oxygen with chemical formula ${O_3}$. It is found in gaseous form and is very less stable than${O_2}$. Any element which can react with ozone and split it has the capacity of depleting the ozone layer.

Complete Step by step answer: Ozone is tested with the help of mercury i.e $Hg$. The process by which ozone is tested with the help of mercury is known as tailing of mercury. During the process of tailing of mercury, the gas is passed through the mercury. It is the unique property of the ozone that if it goes through the mercury it releases meniscus, the curve formed due to the upper surface of the liquid. It gets stuck to the glass due to the formation of mercury oxide.
The chemical reaction during the tailing of mercury takes place in the following manner: The mercury reacts with ozone and gets oxidised to mercury oxide. This reaction can be represented with the help of the following chemical equation;
$2Hg + {O_3} \to {\rm{ }}H{g_2}O + {O_2}$
This is a redox reaction as both the oxidation and reduction reactions are taking place simultaneously. The mercury is getting oxidised to the mercury oxide as well as the ozone is getting reduced to the diatomic oxygen.

Hence, option (B) $Hg$ , is the correct option.

Note: The presence of ozone can be tested with the help of mercury. The process involved is known as tailing of mercury which is a redox reaction. During this process, the ozone acts as an oxidising agent and oxidises the mercury to its oxide and itself gets reduced to diatomic oxygen.