question_answer 22)

Explain with the help of a suitable example polar covalent bond.

Answer:

In heteronuclear diatomic molecules, both the atoms joined by the covalent bond possess different electronegativity. As a result, the atom having higher value of electronegativity attracts the shared electron pair much more strongly than the other atom. For example, in HF the electron pair is more attracted towards F as it is more electronegative than hydrogen. Due to this, fluorine end of the molecule appears negative and hydrogen end positive. Such molecule having two oppositely charged poles are called polar molecules and the bond is said to be a polar covalent bond.