Ion-Dipole Interactions in Aqueous Solutions

Steps:

• Water is a polar molecule with a permanent dipole moment due to its bent structure and electronegativity difference.
• Metal cations are positively charged ions in solution.
• The attraction occurs between the ion's full charge and the dipole's partial charges on water.
• This specific interaction solvates the cation, surrounding it with oriented water molecules.

Why C is correct:

• Ion-dipole interactions are defined as electrostatic attractions between a charged ion and the oppositely charged end of a polar molecule's dipole, as in the hydration of metal cations by water.

Why the others are wrong:

• A: Dipole-dipole interactions occur between two polar molecules, not between an ion and a polar molecule.
• B: Hydrogen bonds are a type of dipole-dipole interaction involving hydrogen attached to N, O, or F, not direct bonding to metal cations.
• D: Ionic bonds form between two ions through electrostatic forces, not between an ion and a neutral molecule like water.

Final answer: C