Formation of the Ionic Bond in NaF

In the formation of the ionic bond, the sodium atom loses the electron from its 3 subshell, thereby becoming Na.  

On the other hand, the fluorine atom takes the electron that is being lost fiom the sodium atom to form a (F ) fluoride ion. 

These resulting ions are oppositely charged and therefore have electrostatic attractive forces between them, resulting in the formation of the ionic bond. 

The attractive energy in an ionic bond can be expressed in terms of Coulombic energy, according to Coulomb s law. Imagine this by considering that the ions are spherical and are separated by particular distances. The attractive energy can be expressed as follows  

A covalent bond is formed as a result of the sharing of a pair of electrons between atoms. Covalent bonds result when the difference in electronegativities between the bonding atoms is very small. Though the intramolecular bonds of covalent compounds are significant, the intermolecular forces are relatively weak. Because of this, covalent compounds have relatively lower boiling and melting points when compared to ionic compoimds. 

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