Phase Changes and Heating Curve of Water

Temperature Temperature – the measure of particles moving Higher temperature = Fast moving particles Lower temperature = Slow moving particles

Thermal Energy Thermal Energy – TOTAL energy of all particles (KE + PE) ALL matter has thermal energy

Heat Heat – the amount of thermal energy that is transferred to an object or area EX: Cooking an egg (Hot stove  frying pan  egg

4 States of Matter Solid Liquid Gas Plasma States of Matter

Phase Properties Phase Atoms Packed Energy Solid Closest Little Liquid Moderate Gas Far A Lot

As heat is added or taken, matter can change its state or phase Phase Changes

Phase Changes Changes States Involved Melting Solid → Liquid Freezing Liquid → Solid Vaporization Liquid → Gas Condensation Gas → Liquid Sublimation Solid → Gas Deposition Gas → Solid

Phase Changes

Heat Transmission Endothermic – Heat goes INTO an object or reaction. Exothermic – Heat is RELEASED from an object or reaction.

Heating Curve of Water Water is matter that can go through ALL the different phase changes

Heating Curve of Water There is NO temperature change during a Change of Phase!

What is the phase change called from B to C? Which letters represent a gas? What is the phase change called from D to E? Which letters represent a solid? What is the phase change called from E to D? What is the phase change called from C to B? What is the temperature change when a phase change occurs?

Heat of Fusion Energy required to change a solid at its melting point to a liquid. It is unique for every substance. For water, the heat of fusion = 6 kJ/mol

Heat of Vaporization The energy required to change a liquid at its boiling point to a gas. It is unique for every substance. For water, the heat of fusion = 41 kJ/mol

Professor Dave Phase Changes Video