Question

A covalent bond in which electrons are shared unequally is

Answer 1

A covalent bond in which electrons are shared unequally is called polar covalent bond.

$\bold{COVALENT \: BOND}$

The bond formed between two or more non metals by sharing of electrons is called covalent bond.  

▶This bond between elements is held by weak wander wall's force.  

$\bold{Formation}$

▶Metals have valency +1 , +2 and +3 so if they are to form any compound they loses their electrons and are held strong electrostatic force.  

▶Non metals have valency  -1 , -2 ,-3 , so they wanna gain 1,2 or 3 electrons,so it either gains electrons from a metal or shares electrons among itself to be stable.

Like in Nitrogen

• Nitrogen have valency -3 .It means it need 3 electrons so either it will form a compound by gaining three electrons from a metal with valency +3 .

• It can also  share its 3 electron with other nitrogen atom .In this the number of shared by one nitrogen atom is equal to the number of atoms shared by other nitrogen atom.So the compound formed is non polar.

• While in case of formation of $NH_3$  or etc, the number of electrons shared by electrons by hydrogen atoms differes from the atoms shared by nitrogen.So. the bond formed will be polar bond as the electrons shared are unequally distributed.

             

Answer 2

A covalent bond in which electrons are shared unequally is called polar covalent bond.