Science, Tech, Math › Science What Is the Freezing Point of Water? Temperature of Freezing Water from a Liquid to a Solid Share Flipboard Email Print ThoughtCo / Hilary Allison Science Chemistry Basics Chemical Laws 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 October 08, 2019 What is the freezing point of water or the melting point of water? Are the freezing point and melting point the same? Are there any factors that affect the freezing point of water? Here's a look at the answers to these common questions. The freezing point or melting point of water is the temperature at which water changes phase from a liquid to a solid or vice versa. The freezing point describes the liquid to solid transition while the melting point is the temperature at which water goes from a solid (ice) to liquid water. In theory, the two temperatures would be the same, but liquids can be supercooled beyond their freezing points so that they don't solidify until well below freezing point. Ordinarily, the freezing point of water and melting point is 0 °C or 32 °F. The temperature may be lower if supercooling occurs or if there are impurities present in the water which could cause freezing point depression to occur. Under certain conditions, water may remain a liquid as cold as -40 to -42°F! How can water remain a liquid so far below its usual freezing point? The answer is that water needs a seed crystal or other small particle (nucleus) on which to form crystals. While dust or impurities normally offer a nucleus, very pure water won't crystallize until the structure of liquid water molecules approaches that of solid ice.