Question

What is the symbol for an element that is halogen?

Answer 1

We must remember that in the periodic table totally $118$ elements are present now. In periodic table eighteen groups and seven periods. In the periodic table the seventeenth group is the halogen group. In this group, four elements are considered as halogen out of five elements in the column. There are fluorine, chlorine, bromine and iodine considered as halogen in the modern periodic table.

Complete step by step answer:
As we know that in chemical reactions, specific symbols are used to represent the group in the reaction. In this way some groups have some special letter or symbol in the periodic table to represent the chemical reaction. Especially metal and halogen having the specific symbol for representation in the chemical reaction. Metals are represented as $M$and halogen are represented as $X$ in the chemical reaction.
The symbol of $X$ is used for an element that is halogen in the chemical reaction.

Note: We have to remember that the symbol of $X$ is used for an element, there are fluorine, chlorine, iodine and bromine in the chemical reaction. The symbol of $M$ is used as metal, such as sodium, potassium, lithium, copper etc,. Halogen is the most electron affinity group in the periodic table. Halogen is also the most electronegativity group in the periodic table. The ionisation energy of the halogen is very less compared to other groups. In halogen from top to bottom, electron affinity decreases. Chlorine is the highest electron affinity species in the periodic table, because the size of the fluorine is very small compared to chlorine. But, the electronegativity value of fluorine is high compared to the electronegativity value of the chlorine.