Which compound would you expect to have greater surface tension: acetone (CH_3)_2CO or water H_2O?

• A. Water (H_2O)
• B. Acetone ((CH_3)_2CO)

Answer: (A)

Verified step by step guidance

1. Understand that surface tension is a measure of the cohesive forces between molecules at the surface of a liquid. Stronger intermolecular forces result in higher surface tension.
2. Identify the types of intermolecular forces present in each compound: Water (H_2O) exhibits hydrogen bonding due to the highly polar O-H bonds, while acetone ((CH_3)_2CO) primarily exhibits dipole-dipole interactions and weaker London dispersion forces.
3. Recall that hydrogen bonding is generally stronger than dipole-dipole interactions and London dispersion forces, leading to greater cohesion between water molecules at the surface.
4. Conclude that because water molecules are held together more strongly by hydrogen bonds, water will have a higher surface tension compared to acetone, which lacks hydrogen bonding.
5. Summarize that the presence and strength of hydrogen bonding in water is the key reason it has greater surface tension than acetone.