Question

What are halogens? Where are they located in the periodic table?

Answer 1

Halogens generally refers to the term salt producing as when they react with metals they produce salts. There are 5 halogens present in the periodic table which are named as fluorine, chlorine, bromine, iodine and astatine.

Complete step by step answer:
There are only 5 halogens present in the periodic table and according to IUPAC nomenclature halogens are termed as group 17 elements. The group of halogens is the only group in the periodic table which contains elements in all the three states of matter i.e. solid, liquid and gas at standard temperature and pressure. All of the halogens form acids when bonded to hydrogen.
The halogens have seven valence electrons in their outermost energy level so they can easily gain an electron by reacting with atoms of other elements to satisfy the octet rule. Mostly halogens are generally produced from minerals or salts. The middle halogens named as chlorine, bromine, and iodine are often used as disinfectants. As we move down the group, the reactivity of elements decreases because of the increasing size of the atoms i.e. fluorine is most reactive halogen while astatine is lesser as compared to other halogens. Halogens are highly reactive in nature and they can be harmful for biological organisms in sufficient quantities. High reactivity of halogens can be explained on the basis of high electronegativity of the atoms due to their high effective nuclear charge.

Note: Other than halogens there is also a known term used interhalogen compounds which are present in the form $X{{Y}_{n}}$ where X and Y both are halogens and n represents the number of halogen present it can be 1,3,5 and 7.