Science, Tech, Math › Science Evaporation Definition in Chemistry What Does Evaporation Mean in Chemistry? Share Flipboard Email Print Evaporation is the phase change from the liquid to gas phase. Jose A. Bernat Bacete, Getty Images Science Chemistry Chemical Laws Basics Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated July 03, 2019 Evaporation is the process by which molecules undergo the a spontaneous transition from the liquid phase to the gas phase. Evaporation is the opposite of condensation. For evaporation to occur, molecules in a liquid must be near the surface, must be moving away from the body of the liquid, and must have enough kinetic energy to escape the interface. When molecules do escape, the average kinetic energy of the remaining molecules is lowered. This lowers the temperature of the liquid and is the basis for the phenomenon of evaporative cooling. Example The gradual drying of damp clothes is caused by the evaporation of water into water vapor. Source Silberberg, Martin A. (2006). Chemistry (4th ed.). New York: McGraw-Hill. pp. 431–434. ISBN 0-07-296439-1.