Which intermolecular force is primarily responsible for water's unusually high surface tension?

• A. Dipole-dipole interactions
• B. London dispersion forces
• C. Ionic bonding
• D. Hydrogen bonding

Answer: (D)

Verified step by step guidance

1. Identify the types of intermolecular forces present in water: London dispersion forces, dipole-dipole interactions, and hydrogen bonding.
2. Recall that water is a polar molecule with a bent shape, leading to a permanent dipole moment, which allows dipole-dipole interactions.
3. Understand that hydrogen bonding is a special, stronger type of dipole-dipole interaction that occurs when hydrogen is bonded to highly electronegative atoms like oxygen, nitrogen, or fluorine.
4. Recognize that water molecules form hydrogen bonds between the hydrogen atom of one molecule and the oxygen atom of another, creating a strong network of interactions.
5. Conclude that this extensive hydrogen bonding network is primarily responsible for water's unusually high surface tension, as it holds the molecules tightly together at the surface.