Physical Phase Changes

Physical Changes in Matter Matter can change physically It however will remain the same substance, but in a different form. Examples: melting, freezing, boiling

Phase Change Diagram

Phase Change Diagram Plateau - Temperature does not increase

absorbs heat energy as atoms speed up Melting Point solid turns to liquid absorbs heat energy as atoms speed up ex. Ice melts at 0°Celsius

Freezing point liquid turns to solid releases heat energy as atoms slow down ex. Water freezes at 0°Celsius

Decrease in Temperature

Vaporization Boiling Change of state from liquid to a gas occurs at a liquid’s boiling point and occurs throughout the liquid. Ex. Water boils at 100 ° C

Evaporation Vaporization water evaporates slowly from the surface of the liquid. Ex. Water absorbs energy from your skin, you feel cooler

Temperature Increases

Sublimation Process of changing a solid to a gas directly without the liquid stage. Absorbs heat as atoms increase speed. Ex: Dry ice (frozen CO2) sublimes

Condensation Process of changing a gas to a liquid. Releases heat as atoms slow down. Example: water condenses on mirror when taking a hot shower.

Phase Diagram D E C B A

Exothermic reaction- chemical reaction in which energy is released or removed. Cold reaction Endothermic reaction- chemical reaction in which energy is absorbed. Hot Rx.