Question

Write two uses of $Cl{{O}_{2}}$.

Answer 1

Hint: $Cl{{O}_{2}}$ or chlorine dioxide is a chemical compound that exists as a gas that is yellowish-green in color at a temperature above 11${}^\circ C$. At a temperature between -59${}^\circ C$ and 11${}^\circ C$, it exists as a reddish-brown liquid, and at a temperature below -59${}^\circ C$, it exists as a bright orange crystal.

Complete answer:
Now, since chlorine dioxide ($Cl{{O}_{2}}$) can transfer oxygen atoms to various molecules, and gains electrons during redox (oxidation-reduction) reactions, it acts as an oxidizing agent.
Let us look at the uses of chlorine dioxide ($Cl{{O}_{2}}$)
- Bleaching
The bleaching of wood pulp can be done by chlorine dioxide ($Cl{{O}_{2}}$) either in combination with chlorine or alone in ECF bleaching sequences (elemental chlorine-free).
Chlorine dioxide ($Cl{{O}_{2}}$) minimized the production of organochlorine compounds and the process takes place at a pH range between 3.6 to 6.
The ECF technology (chlorine dioxide ($Cl{{O}_{2}}$)) is one of the most important methods of bleaching in the world and is extensively used in paper industries. For example, 95% of kraft pulp or cardboard is bleached using chlorine dioxide ($Cl{{O}_{2}}$) in ECF bleaching sequences.
Flour is also bleached using chlorine dioxide.
 - Water Treatment
Chlorine dioxide ($Cl{{O}_{2}}$) is used before chlorination of drinking water as a pre-oxidant to destroy the impurities in natural water.
Without the use of chlorine dioxide ($Cl{{O}_{2}}$), suspected carcinogenic trihalomethanes are formed when organic impurities in raw water interact with free chlorine. This is why chlorine dioxide ($Cl{{O}_{2}}$) is considered to be better than chlorine when in the presence of amines and ammonia and at a pH above 7.

Note:
Some other uses of chlorine dioxide ($Cl{{O}_{2}}$) include
- oxidizer
- disinfectant
- pseudo medicine
- destroying phenols in wastewater
- odor control
While there are multiple uses of chlorine dioxide ($Cl{{O}_{2}}$), it should be noted that it has often been falsely said to cure diseases like COVID-19 and childhood autism through ingestion.