Question

What covalent compound is ${{N}_{2}}S$?

Answer 1

Covalent compounds are compounds that consist of covalent bond between their atoms. A covalent bond is formed when the atoms in the molecule share the valence electrons with each other to form bonds. The covalent compounds can be classified on the basis of their polarities.

Complete answer:
A covalent compound is that compound in which the atoms are held together by covalent bonds. Covalent bonds are the bonds formed by sharing of electrons between atoms in a molecule. The electrons are shared in between the atoms of variable electronegativities. There are two types of covalent compounds, polar and non – polar covalent compounds. Polar covalent compounds consist of electron pairs with uneven distribution to form bonds, these types of compounds consist of atoms having a difference in electronegativity. While non – polar covalent compounds consist of equal distribution of electron pairs in forming bonds, they have no difference in the electronegativity values of the atoms.
We have been given a molecule, ${{N}_{2}}S$ which is dinitrogen sulfide. This compound consists of nitrogen and sulfur that have differences in their electronegativities. Nitrogen is more electronegative than sulfur due to its small size. This results in polarity in the molecule.
Now, the Lewis structure of ${{N}_{2}}S$ shows the distribution of electrons as, $:N\equiv N-\underset{\centerdot \centerdot }{\overset{\centerdot \centerdot }{\mathop{S}}}\,:$ , this shows that there is uneven distribution of the valence electrons. This makes the ${{N}_{2}}S$ molecule polar.
Hence, ${{N}_{2}}S$ molecule is a polar covalent compound.

Note:
The non – polar covalent compounds are gases like, hydrogen gas ${{H}_{2}}$, nitrogen gas ${{N}_{2}}$. They are non – polar as they do not have electronegativity differences. The ${{N}_{2}}S$ molecule resembles ${{N}_{2}}O$ molecule as sulfur and oxygen are from the same group with the same valence electrons. The shape of ${{N}_{2}}S$ molecule according to VSEPR is linear.