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Notes: Thermal Energy and Phase Changes. 150 100 50 0. Temperature (°C). 0 1 2 3 4 5 Thermal Energy (Heat). Adding Thermal Energy to H 2 0. 150 100 50 0. Temperature (°C). Ice.
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Notes: Thermal Energy and Phase Changes 150 100 50 0 Temperature (°C) 0 1 2 3 4 5 Thermal Energy (Heat)
Adding Thermal Energy to H20 150 100 50 0 Temperature (°C) Ice 0 1 2 3 4 5 Thermal Energy
Adding Thermal Energy to H20 150 100 50 0 Temperature (°C) Melting Ice 0 1 2 3 4 5 Thermal Energy
Adding Thermal Energy to H20 150 100 50 0 Temperature (°C) Water Melting Ice 0 1 2 3 4 5 Thermal Energy
Adding Thermal Energy to H20 150 100 50 0 Vaporization Temperature (°C) Water Melting Ice 0 1 2 3 4 5 Thermal Energy
Adding Thermal Energy to H20 150 100 50 0 Vapor Vaporization Temperature (°C) Water Melting Ice 0 1 2 3 4 5 Thermal Energy
Taking Thermal Energy from H20 150 100 50 0 Vapor Temperature (°C) 0 1 2 3 4 5 Thermal Energy
Taking Thermal Energy from H20 150 100 50 0 Vapor Condensation Temperature (°C) 0 1 2 3 4 5 Thermal Energy
Taking Thermal Energy from H20 150 100 50 0 Vapor Condensation Temperature (°C) Water 0 1 2 3 4 5 Thermal Energy
Taking Thermal Energy from H20 150 100 50 0 Vapor Condensation Temperature (°C) Water Freezing 0 1 2 3 4 5 Thermal Energy
Taking Thermal Energy from H20 150 100 50 0 Vapor Condensation Temperature (°C) Water Freezing Ice 0 1 2 3 4 5 Thermal Energy
Thermal Energy and Phase Changes 150 100 50 0 Gas Vaporization Condensation Temperature (°C) Liquid Melting Freezing Solid 0 1 2 3 4 5 Thermal Energy
Rules of Thumb 1) Horizontal lines are phase changes 2) Diagonal lines are changes in temperature 3) Adding heat causes different phase changes than removing it!
VAPORIZATION (Liquid-Gas) • evaporation – a change in phase from liquid to gas at the surface. • this cools the remaining liquid! • boiling – a change in phase from liquid to gas below the surface. • this cools the remaining liquid! • boiling point – the temperature that an object vaporizes or condenses.
Condensation (Gas Liquid) • this is a warming process for the liquid. • gas molecules strike surface of liquid and give up so much energy that they can’t stay in gaseous phase • examples droplets forming on mirror droplets on glass of water
Phase Change Process (S & L) • melting – thermal energy is used to break bonds • the bonds that hold molecules in vibrating lattice structure are breaking. • the intermolecular forces lessen • freezing – thermal energy is used to create bonds and hold molecules in place • the bonds that will hold molecules in position are forming • the intermolecular forces increase • melting point – the temperature at which an object either melts or freezes.