Which intermolecular force is primarily responsible for the phenomenon of surface tension in liquids?

• A. Hydrogen bonding
• B. Ionic bonding
• C. Metallic bonding
• D. London dispersion forces

Answer: (A)

Verified step by step guidance

1. Understand that surface tension in liquids arises due to the cohesive forces between molecules at the surface, which cause the surface to behave like a stretched elastic membrane.
2. Identify the types of intermolecular forces: ionic bonding (strong electrostatic attraction between ions), metallic bonding (delocalized electrons in metals), London dispersion forces (weak temporary dipoles in all molecules), and hydrogen bonding (strong dipole-dipole interaction involving H bonded to N, O, or F).
3. Recognize that ionic and metallic bonding are not typical intermolecular forces in liquids but rather types of bonding within solids or metals, so they are unlikely to be responsible for surface tension in common liquids.
4. Compare London dispersion forces and hydrogen bonding: London forces are generally weaker and present in all molecules, while hydrogen bonding is a stronger, specific type of dipole-dipole interaction that significantly increases cohesion between molecules like water.
5. Conclude that hydrogen bonding, due to its strength and directional nature, is primarily responsible for the high surface tension observed in liquids such as water.