Question

Are halogens disinfectants?

Answer 1

Halogens are the class of elements that belongs to group 17 of the periodic table, which includes, fluorine, chlorine, bromine, iodine, and Astatine. And halogens form salt by reacting with a wide range of metals.

Complete step-by-step answer: Before going into the solution for the question, let us first discuss some facts about halogens.
Halogens are elements that belong to group 17 and it has seven valence electrons so it needs only one electron to complete its octet configuration. The name halogens mean salt-forming and justifying the name the elements in group 17 react with many metals like calcium, potassium, sodium, silver, etc., and form its salt.
As we are familiar with, there are five major elements in the group halogens- fluorine, chlorine, bromine, iodine, and astatine. But astatine is a radioactive element so we are concerned about the first four elements.
These halogens are mainly obtained from seawater and in the form of salts and the majority of their compounds exist as ionic. These halogens also bond with hydrogen and form various acids and these are the reasons they act as disinfectants.
Mainly the middle-range halogens like chlorine, bromine, and iodide are commonly used as disinfectants since fluorine is difficult to handle. And the most common halogens that act as a disinfectant are chlorine and iodine.
Halogens are used as disinfectants and antiseptic because they have microbicidal quality (ability to kill microbes) along with microbiostatic nature (ability to prevent from increasing the number of the colony of microbes).
Chlorine when dissolved in water forms the hypochlorous acid, which is a strong oxidant and it easily enters the cell and has the disinfectant and anti-microbial quality because of which it is used as a purifying agent in water plants. It purifies using the mechanism of bleaching. And iodine works by oxidizing cellular components including fatty acids, nucleosides, etc. Iodine solutions are used before surgeries as antiseptic.
So we could say that halogens are used as disinfectants.

Note: Iodine tincture which is used for medical purposes as a disinfectant is the solution made by mixing 2% solution which has iodine and NaI mixed in 70% of alcohol.
The iodine solution sometimes can be irritant to the skin so a strong solution must be avoided.
Fluorine is also used in dentistry as it also has anti-microbial properties to prevent cavities.
Bromine is used to kill pests and insects by spraying bromine solution but it is very harmful to human tissue and its vapors are irritant for the eyes and throat.