A diatomic element is an element in the periodic table, in which a molecule of an element which consists of two atoms bonded together. The diatomic elements are the – ine halogens (i.e. fluorine, chlorine, bromine, Iodine) and elements with a –gen ending (i.e. hydrogen, oxygen, nitrogen). Almost 99% of the Earth’s atmosphere consists of diatomic molecules (nitrogen and oxygen).
Seven pure elements form diatomic molecules. The list of these elements are:
- Hydrogen (H2)
- Nitrogen (N2)
- Oxygen (O2)
- Fluorine (F2)
- Chlorine (Cl2)
- Iodine (I2)
- Bromine (Br2)
An easy way to remember the diatomic elements
is: “Have No Fear Of Ice Cold Beer”.
Other elements can also form diatomic molecules besides the seven mentioned on this list. For example, diatomic compounds comprise of two different elements such as HCl, NaCl, and KBr. In contrast, monatomic elements include single atoms such as Ar, He.
Except for the following five elements gases which are found as diatomic molecules at room temperature and pressure, all of the diatomic elements are types of nonmetals:
- Hydrogen – H2
- Nitrogen – N2
- Oxygen – O2
- Fluorine – F2
- Chlorine – Cl2
Bromine and Iodine is a liquid at room temperature, and as the temperature is lowered or increased under pressure, the other elements become diatomic liquids.
