Question

Is $NaCl$ a pure covalent bond?

Answer 1

Hint: Ionic bonds involve transfer of electrons from one atom to another. Covalent bond involves sharing of electrons between the two atoms. If the electronegativity difference between two elements is less than $1.5$ , then the bond is covalent and if the difference is greater than $1.5$ , then the bond is ionic.

Complete answer:
When atoms of different elements combine together, they form compounds.
Sodium chloride ($NaCl$) is made up of sodium and chlorine. Let’s see their configurations in order to understand the bond between them.
$Na = 1{s^2}2{s^2}2{p^6}3{s^1}$
$Cl = 1{s^2}2{s^2}2{p^6}3{s^2}3{p^5}$
In order to attain stable outermost electronic configuration, Sodium can lose $1{e^ - }$ easily to form $N{a^ + }$ . Chlorine on the other hand can easily gain $1{e^ - }$ to attain stable configuration forming $C{l^ - }$.
Sodium transfers its outermost electron to chlorine, forming ions that are electrically attracted to each other. Thus, forming ionic bonds.
$N{a^ + }C{l^ - }$
In this way both atoms will have stable outermost electronic configuration.
Also, the electronegativity difference between both the atoms is greater than $1.5$ . Sodium is an electropositive element while chlorine is an electronegative element. This also indicates the formation of an Ionic bond.
Thus, we can say that $NaCl$ doesn’t have a covalent bond (which involves sharing of electrons between two atoms) rather $NaCl$ forms an Ionic bond.

Note:
We have seen that sodium is highly electropositive that means it can easily lose electrons, while chlorine is highly electronegative. It will attract the electron towards itself leading to transfer of electrons from sodium to chlorine forming ionic bonds. Methane ($C{H_4}$) forms covalent bonds where there is sharing of electrons between carbon and hydrogen.