Which term refers to the attraction between water molecules?

Which term refers to the attraction between water molecules?

• A. Adhesion
• B. Cohesion
• C. Osmosis
• D. Capillarity

Answer: (B)

Understanding how water molecules stick to each other is about cohesion. Water is a polar molecule, so it forms hydrogen bonds with neighboring water molecules. These attractions between like molecules pull them together, giving water strong cohesion. This is the reason water forms droplets and has surface tension, and it helps explain why water can rise a bit in narrow tubes when combined with the adhesive attraction to the tube walls. Adhesion, on the other hand, is the attraction between water and other materials, such as glass. Osmosis is the movement of water across a semipermeable membrane driven by solute differences, not by the attraction between water molecules. Capillarity describes the overall rise of liquids in small spaces due to cohesive and adhesive forces, but it’s the combination of those forces, not the specific attraction between water molecules alone, that explains capillary action.

Understanding how water molecules stick to each other is about cohesion. Water is a polar molecule, so it forms hydrogen bonds with neighboring water molecules. These attractions between like molecules pull them together, giving water strong cohesion. This is the reason water forms droplets and has surface tension, and it helps explain why water can rise a bit in narrow tubes when combined with the adhesive attraction to the tube walls.

Adhesion, on the other hand, is the attraction between water and other materials, such as glass. Osmosis is the movement of water across a semipermeable membrane driven by solute differences, not by the attraction between water molecules. Capillarity describes the overall rise of liquids in small spaces due to cohesive and adhesive forces, but it’s the combination of those forces, not the specific attraction between water molecules alone, that explains capillary action.