The ICl molecule consists of an iodine atom and a chlorine atom bonded together. Both iodine and chlorine are non-metals, so the bond between them is covalent. However, they have different electronegativities, leading to a polar covalent bond.

Concept: Electronegativity and Polarity

Electronegativity is the ability of an atom in a chemical compound to attract a shared pair of electrons towards itself. The difference in electronegativity between two bonded atoms determines the polarity of the bond. If the electronegativity difference is significant, the bond is polar, with the more electronegative atom acquiring a partial negative charge (${\delta }^{-}$) and the less electronegative atom acquiring a partial positive charge (${\delta }^{+}$).

Why (C) is correct:

1. Electronegativity Comparison: Chlorine (3.16 on Pauling scale) is more electronegative than iodine (2.66 on Pauling scale).

2. Electron Shift: Due to the higher electronegativity of chlorine, the shared pair of electrons in the I-Cl bond will be pulled closer to the chlorine atom.

3. Polarity: This unequal sharing of electrons results in the chlorine atom acquiring a partial negative charge (${\delta }^{-}$) and the iodine atom acquiring a partial positive charge (${\delta }^{+}$). Therefore, the molecule is polar with the negative end on chlorine.

Option Analysis:

• A) purely covalent: Incorrect. While it is a covalent bond, the significant electronegativity difference makes it polar, not purely covalent. Purely covalent bonds occur between atoms of identical electronegativity (e.g., ${\text{Cl}}_2$).
• B) purely electrovalent: Incorrect. Electrovalent (ionic) bonds form between a metal and a non-metal, involving a complete transfer of electrons. ICl is formed between two non-metals.
• D) polar with negative end on iodine: Incorrect. Iodine is less electronegative than chlorine, so it will acquire a partial positive charge, not a partial negative charge.

Correct Answer: (C)