Presentation on theme: "Phase Changes. Where is this used? Conditioning of buildings, such as 'ice-storage' Cooling of heat and electrical engines Cooling: food, beverages, coffee,"— Presentation transcript:
Where is this used? Conditioning of buildings, such as 'ice-storage' Cooling of heat and electrical engines Cooling: food, beverages, coffee, wine, milk products, green houses Medical applications: transportation of blood, operating tables, hot-cold therapies Waste heat recovery Solar power plants Spacecraft thermal systems Thermal comfort in vehicles Thermal protection of electronic devices Thermal protection of food: transport, hotel trade, ice-cream, etc. Textiles used in clothing Computer cooling
What happens during a phase change? During a phase change, heat energy is either absorbed or released. Heat energy is released as molecules slow down and move closer together. Heat energy is absorbed as molecules speed up and expand.
Melting & Boiling Points Melting Point: The temperature at which a solid changes into a liquid. Boiling Point: The temperature at which a liquid changes into a gas. What is a Freezing point? Compare the freezing and melting points of water.
Graphing a Phase Change – Why is there no change in temperature during a phase change? – Define melting and boiling points. – What is the melting point and boiling point of water? – At what temperature does water freeze and become a solid?