Question

which of the following bonds is a polar covalent bond? answer: a li-cl b cl-cl c h-cl d li-li

Explanation:

• For \(Li - Cl\):
• \(Li\) is a metal and \(Cl\) is a non - metal. The bond between a metal and a non - metal is an ionic bond. In an ionic bond, there is a complete transfer of electrons from the metal to the non - metal.
• For \(Cl - Cl\):
• The bond between two identical non - metal atoms (\(Cl\) in this case) is a non - polar covalent bond. Since both atoms have the same electronegativity, the electron pair is shared equally between them.
• For \(H - Cl\):
• \(H\) and \(Cl\) are non - metals. The electronegativity of \(Cl\) (\(3.16\)) is greater than that of \(H\) (\(2.20\)). The difference in electronegativity (\(\Delta\chi=3.16 - 2.20=0.96\)) leads to an unequal sharing of the electron pair. So, the \(H - Cl\) bond is a polar covalent bond.
• For \(Li - Li\):
• The bond between two identical metal atoms (\(Li\) here) is a metallic bond. Metallic bonds involve a sea of delocalized electrons among the metal cations.

Answer:

C. \(H - Cl\)