Question

The polarity of a covalent bond between two atoms depends upon
(A) Atomic size
(B) Electronegativity
(C) Ionic size
(D) None of the above

Answer 1

Hint: A covalent bond is formed by the mutual sharing of one or more electron pairs between the atoms. A covalent bond can be a single bond, double bond or triple bond. A single bond is a sigma bond. In double and triple bonds, one bond is a sigma bond, and the others are known as pi-bonds.

Complete Step by Step Answer:
The bond is said to be polar if there is an electronegativity difference between the two atoms forming the bond. The greater the difference in electronegativity, the greater the polarity of a bond. When a bond is polar, one atom of the bond has a tendency to attract the shared pair of electrons; that is, there is unequal sharing of the bond.

When a covalent bond has an unequal share of electrons, it is said to be a polar covalent bond, whereas when a covalent bond has an equal share of electrons, it is said to be a nonpolar covalent bond. However, if the two bonds have a large difference in electronegativity, then the bond will be an ionic bond.

Hence, the polarity of a covalent bond between two atoms depends upon the electronegativity of the two atoms.
Correct Option: (B) Electronegativity.

Note: The ionic size is the size of ions formed by the metal formed by the gain or loss of electrons. The atomic size is the distance between the centre of the nucleus and the outermost shell of the atom. The polarity of a covalent bond does not depend upon the ionic or atomic size.