Science, Tech, Math › Science Phase Change Definition Print The boiling point of water is is the phase change from the liquid to vapor state. Jody Dole / 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. 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. Learn about our Editorial Process Updated on February 04, 2019 Definition: A phase change is a change in the state of matter of a sample. A phase change is an example of a physical change. Read More Phase Definition and Examples By Anne Marie Helmenstine, Ph.D. Also Known As: phase transition Examples: An example of a phase change is water changing from a liquid to vapor. Another example of a phase change is melted wax cooling into solid wax. Cite this Article Format mla apa chicago Your Citation Helmenstine, Anne Marie, Ph.D. "Phase Change Definition." ThoughtCo, Apr. 5, 2023, thoughtco.com/definition-of-phase-change-605905. Helmenstine, Anne Marie, Ph.D. (2023, April 5). Phase Change Definition. Retrieved from https://www.thoughtco.com/definition-of-phase-change-605905 Helmenstine, Anne Marie, Ph.D. "Phase Change Definition." ThoughtCo. https://www.thoughtco.com/definition-of-phase-change-605905 (accessed April 24, 2024). copy citation