Fluorine (`~F_2` ) reacts with hydrogen (`~H_2` ) to form the compound hydrogen fluoride (`~HF` ) as shown in the reaction below:

`~F_2 + ~H_2 -gt 2HF`

The bonds formed between H atoms and F atoms are covalent bonds. The electrons in a covalent bond are shared between the atoms. Covalent bonds can be composed of two shared electrons, four shared electrons, or six shared electrons. A covalent bond that is composed of two shared electrons is called a single bond. A covalent bond that is composed of four shared electrons is called a double bond. A covalent bond that is composed of six shared electrons is called a triple bond. The covalent bonds formed between H and F atoms are examples of single bonds.