What term describes water changing from liquid to vapour when heated?

What term describes water changing from liquid to vapour when heated?

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

Answer: (B)

Evaporation is the process where water changes from liquid to vapour as energy is added. Molecules at the surface gain enough energy to overcome the forces holding them in the liquid and escape into the air as water vapour. This can happen at any temperature, not just when water boils, so it occurs gradually on the surface. Condensation is the reverse (gas to liquid), sublimation is solid to gas, and precipitation is water falling as rain or snow. Evaporation is also a cooling process because the higher-energy molecules leave the liquid.

Evaporation is the process where water changes from liquid to vapour as energy is added. Molecules at the surface gain enough energy to overcome the forces holding them in the liquid and escape into the air as water vapour. This can happen at any temperature, not just when water boils, so it occurs gradually on the surface. Condensation is the reverse (gas to liquid), sublimation is solid to gas, and precipitation is water falling as rain or snow. Evaporation is also a cooling process because the higher-energy molecules leave the liquid.