Water has surface tension because:

• A. strong hydrogen bonding between water molecules creates cohesive forces at the surface
• B. water molecules at the surface have higher kinetic energy than those in the bulk
• C. water molecules are repelled from the surface by air molecules
• D. ionic bonds form between water molecules at the surface

Answer: (A)

Verified step by step guidance

1. Understand that surface tension is a property of liquids that arises due to the cohesive forces between molecules at the surface.
2. Recall that water molecules are polar and can form hydrogen bonds, which are strong intermolecular forces compared to other types of interactions.
3. Recognize that at the surface, water molecules experience a net inward force because they are attracted to other water molecules below and beside them, creating a 'tight' surface layer.
4. Eliminate options that do not align with the nature of water's intermolecular forces: water molecules do not have higher kinetic energy at the surface, are not repelled by air molecules, and do not form ionic bonds with each other.
5. Conclude that the strong hydrogen bonding between water molecules creates cohesive forces at the surface, which is the reason for water's surface tension.