Which process results when water vapor changes to a liquid, forming droplets on a cold surface?

Which process results when water vapor changes to a liquid, forming droplets on a cold surface?

• A. Condensation
• B. Evaporation
• C. Melting
• D. Sublimation

Answer: (A)

Condensation occurs when water vapor in the air loses enough energy to become a liquid, especially as it meets a surface that is cooler than the surrounding air. The cold surface lowers the vapor’s energy, causing the gas molecules to slow and stick together, forming tiny liquid droplets—this is why you see dew on a cold window or beads on a chilled glass. This happens when the air is near or at its dew point, so the vapor can no longer stay as a gas. Evaporation would be liquid turning into vapor, typically when a liquid is exposed to warmth or reduced pressure. Melting is solid turning into liquid. Sublimation is solid turning directly into gas. Hence condensation is the process that forms droplets on a cold surface.

Condensation occurs when water vapor in the air loses enough energy to become a liquid, especially as it meets a surface that is cooler than the surrounding air. The cold surface lowers the vapor’s energy, causing the gas molecules to slow and stick together, forming tiny liquid droplets—this is why you see dew on a cold window or beads on a chilled glass. This happens when the air is near or at its dew point, so the vapor can no longer stay as a gas.

Evaporation would be liquid turning into vapor, typically when a liquid is exposed to warmth or reduced pressure. Melting is solid turning into liquid. Sublimation is solid turning directly into gas. Hence condensation is the process that forms droplets on a cold surface.