Matter- Physical Transformations

Review from last class… Bill Nye- Phases of Matter (Finish correcting)

Phases of Matter- Changes

Phases of Matter- Transformations Energy (heat) causes matter to change state By adding energy you can change solidsliquids and liquidsgases By removing energy you can change gasesliquids and liquids solids

Phase Changes: Adding Energy Solid  Liquid: Melting Temperature at which it changes is called Melting Point Liquid  Gas: Boiling/Evaporating Temperature at which it changes is called Boiling Point Adding energy speeds up molecules and increases their movement

Phase Changes: Removing Energy Gas  Liquid: Condensation Same temperature as the Boiling point Liquid  Solid: Freezing Same temperature as the Melting point Removing energy causes the particles to slow down and decreases their movement

Phase Changes: Solids to Gases Some solids can completely “skip” the liquid phase and change from solid gas or from gas solid This is called Sublimation and Deposition Iodine: https://www.youtube.com/watch?v=Ft2KgtlP8Lk Dry Ice: https://www.youtube.com/watch?v=QhTekm5NdiE

Physical Transformations Any change of state (phase) is considered a physical transformation The composition of the molecule doesn’t change just what state it is in Ex: Ice is made of H2O molecules, when heated, the H2O molecules stay H2O, only the speed they are moving and their positioning changes http://www.middleschoolchemistry.com/multimedia/chapter2/lesson4#ice_bomb http://www.middleschoolchemistry.com/multimedia/chapter2/lesson5#melting_ice

Heating Curve for Water The flat line on a heating curve represents a change of state The sloped line on a heating curve represents a change in temperature

Learning Check 1 A. Water condenses at a temperature of 1) 0°C 2) 50°C 3) 100°C B. At a temperature of 0°C, water 1) freezes 2) melts 3) changes to a gas C. When a gas condenses, heat is 1) applied 2) removed

Solution 1 A. Water condenses at a temperature of 3) 100°C B. At a temperature of 0°C, water 1) freezes 2) melts C. When a gas condenses, heat is 1) removed

Learning Check 2 Is energy applied (1) or removed (2) in each of the following: ____A. Ice to liquid water ____B. Water vapor to rain ____C. Water to ice When it rains, the air becomes 1) warmer 2) cooler 3) does not change

Solution 2 Is energy absorbed (1) or released (2) in each of the following: A. Ice to liquid water 1 B. Water vapor to rain 2 C. Water to ice When it rains, the air becomes 1) warmer

Learning Check 3 Complete using the terms gains or loses In the cooling coils of a refrigerator, liquid Freon ___________ heat from the food and changes to a gas Food ___________heat and becomes colder In the back of the refrigerator, Freon _________ heat and condenses back to a liquid

Solution 3 Complete using the terms gains or loses In the cooling coils of a refrigerator, liquid Freon gains heat from the food and changes to a gas Food loses heat and becomes colder In the back of the refrigerator, Freon loses heat and condenses back to a liquid

Worksheet- Physical Transformations On the back side of the “Phases of Matter-Bill Nye” sheet Complete the questions and hand in to the pass in bin