Science, Tech, Math › Science Deliquescence Definition Share Flipboard Email Print Jenny Downing/Flickr.com/CC 2.0 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 November 25, 2019 The process in which a soluble substance picks up water vapor from the air to form a solution. In order for deliquescence to occur, the vapor pressure of the water in the air must be greater than the vapor pressure of the saturated solution.