Why ionic bond is considered as an extreme case of polar covalent bond?

Explanation

### Step-by-Step Text Solution:

1. **Understanding Ionic Bonds**: Ionic bonds are formed when there is a complete transfer of electrons from one atom to another, resulting in the formation of charged ions. This typically occurs between metals and nonmetals, where the metal donates electrons and the nonmetal accepts them.

2. **Electronegativity Concept**: Electronegativity is the ability of an atom to attract electrons in a chemical bond. Atoms with high electronegativity can pull electrons more strongly compared to those with lower electronegativity.

3. **Polar Covalent Bonds**: In polar covalent bonds, electrons are shared between two atoms, but the sharing is unequal due to a difference in their electronegativities. One atom attracts the shared electrons more than the other, leading to a partial positive charge on one atom and a partial negative charge on the other.

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