Solution:
concept - Only chlorine, out of the group of supplied inorganic elements, has the capacity to eradicate bacteria and other microbes. It functions as a disinfectant and eliminates the bacteria in the water. Thus, it results in wholesome water.There are several ways to manufacture germ-free water molecules, but chlorine disinfection is a convenient and affordable option. Pathogens precipitate as a result of the chlorine treatment of water. So efficiently, filtration is used after chlorine treatment to produce the best-sterilised water.
Additionally, chlorine is utilised to sanitise swimming pools and ponds' water. However, excessive chlorine use causes rashes and itching on the body's skin.
In contrast to chlorine, iodine and bromine do not have the same disinfectant qualities.
As a hypochlorite solution, chlorine is employed. The hypochlorite solution works wonders against a variety of strong germs.
Sulphur also lacks chlorine's capacity for disinfection. Hypochlorous acid and a hypochlorite ion are produced when sodium hypochlorite dissolves in water. The pathogens are quickly destroyed by the hypochlorite ion. It goes by the name bleach as well.
Therefore, chlorine, a non-metal, is utilised to sanitise water.
Hence, the correct option is 3).
