Phase Changes Slide Show #2

Skip #1 & #2 We’ll get to these later.

Review: Kinetic Energy Not on notes Kinetic Energy is the energy of motion. If an object is moving, or not, it has kinetic energy. Particles that make up an object move.

Temperature and Average KE Not on notes Temperature is the measure of how fast molecules move. Heat involves of how fast and how much molecules. Kinetic Energy is the energy of motion.

Changing States Matter changes when heat energy is added or taken away. The total energy remains the same. Law of conservation of energy!!!

Phase Change Terms Evaporation – Liquid changes to Gas Condensation – Gas changes back to liquid. Freezing – Liquid changes to solid. Melting – Solid changes to liquid. Sublimation – Solid changes directly to gas Deposition – Gas changes back into a solid.

PHASE CHANGES

What’s your point? Melting point is the temperature at which a substance melts. Freezing point is the temperature at which a substance freezes. It is the same temperature!!! (just depends on + heat or –heat). Water freezes & melts at 0 degrees Celsius!!!!

What’s your point? The boiling point is the temperature at which a substance evaporates. The condensation point is the temperature at which a substance condenses. Water boils and condenses at 100 o C. (depends on +heat or –heat).

An easy way to remember

Watch it in Action!!! The Hot Plate!