Diatomic molecule — দ্বি-পরমাণবিক অণু

Definition

A diatomic molecule consists of two atoms bonded together. When both atoms are the same element, like $\mathrm{H_{2}}$, $\mathrm{N_{2}}$ or $\mathrm{O_{2}}$, it is homonuclear; when they differ, like $\mathrm{CO}$ or $\mathrm{HCl}$, it is heteronuclear. Seven elements refuse to live single in nature — hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine — so you always write them with a subscript two. This matters in equations: oxygen enters a reaction as $\mathrm{O_{2}}$, never as a lone O atom.

For example

The air filling your lungs right now is about 78% $\mathrm{N_{2}}$ and 21% $\mathrm{O_{2}}$ — nearly every breath you take is a mixture of diatomic molecules.

Elements this touches

Related terms