When two fluorine atoms are joined the bond that forms is a covalent bond
A covalent bond is when the electron is shared between two atoms so that they can complete the octet and be stable
This link tends to occur between atoms of similar electronegativity so that it can be shared between both
In this case two fluorine atoms are joined and there is an electron that is shared between both fluorine atoms so that both can be stable
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As the bond occurs between two exactly the same atoms, the electron is attracted equally because both have the same electronegativity, this type of bond has the name of pure covalent
