Question

What are the group $7$ elements called?

Answer 1

Group 7 contains non-metal elements placed in a vertical column on the right of the periodic table. The elements in group 7 are called the halogens. The group $7$ elements are fluorine, chlorine, bromine, iodine and astatine. The name halogen means salt former, derived from the Greek words halo (salt) and gen (formation).

Complete answer:
Group $7$ of the periodic table are the halogens: fluorine, chlorine, bromine, iodine, and astatine. They have seven valence electrons in their highest energy orbital. This is one electron away from having a full octet of eight electrons, so these elements tend to form anions having $- 1$ charges, known as halides: fluoride, chloride, bromide, and iodide. In combination with other nonmetals, the halogens form compounds through covalent bonding.
In their elemental form, the halogens form diatomic molecules, ${X_2}$ ,connected by single bonds. Since all of the halogens have one unpaired electron in their atomic forms, it is easy for them to pair up to form diatomic molecules. The ${X_2}$ molecules are nonpolar, so the only interactions between them are fairly weak London forces, but as the size of the atoms increase, the London forces become stronger, increasing their melting and boiling point.

Note:
The halogens are extremely reactive, especially fluorine, and are not found naturally in their elemental forms. They are usually found in combination with various metals in minerals, or in combination with other nonmetals in molecular compounds. The halogens form compounds with carbon easily organic molecules containing carbon are often known as alkyl halides and have many different household and industrial uses.