6th Grade: Matter and Energy (Module H) Unit 1 Lessons 4 & 5

Kinetic Theory of Matter Unit 1 Lesson 5 States of Matter Kinetic Theory of Matter “All matter is made of tiny particles that are in constant motion” Copyright © Houghton Mifflin Harcourt Publishing Company 2

Read and do page 66-67 Video: Does hot water freeze faster than cold water - https://www.youtube.com/watch?v=UjIdzcxSe3g

Unit 1 Lesson 5 States of Matter How does particle motion affect the properties of solids, liquids, and gases? What state of matter is shown in the image below? How do you know? Video: Does hot water freeze faster than cold water - https://www.youtube.com/watch?v=UjIdzcxSe3g Copyright © Houghton Mifflin Harcourt Publishing Company 5

Liquids: Crash Course Chemistry – https://www.youtube.com/watch?v=BqQJPCdmIp8

A Change of State Unit 1 Lesson 5 States of Matter By adding or removing heat (energy), we can change the state of matter from one form to another This does not change the identity of the substance, just the appearance Read page 71 Do page 70 together (BEFORE NEXT SLIDE!) Then READ page 76 Copyright © Houghton Mifflin Harcourt Publishing Company 7

What happens when substances change state? Unit 1 Lesson 5 States of Matter What happens when substances change state? What change of state is happening in this diagram? Copyright © Houghton Mifflin Harcourt Publishing Company 8

Changes of State 1. Freezing – liquid becomes a solid Unit 1 Lesson 5 States of Matter 1. Freezing – liquid becomes a solid Take away heat (substance loses energy) particles slow down, lock into fixed arrangement The TEMPERATURE at which something changes from liquid to solid is called freezing point Read and do page 78 Copyright © Houghton Mifflin Harcourt Publishing Company 9

Changes of State 2. Melting - solid becomes a liquid Unit 1 Lesson 5 States of Matter Changes of State 2. Melting - solid becomes a liquid Add heat, speed up vibrations in particles Attraction between particles decreases, particles slide past each other The TEMPERATURE at which substances change from solid to liquid is called melting point Read and do page 79 Copyright © Houghton Mifflin Harcourt Publishing Company 10

Changes of State 3. Evaporation – liquid becomes gas Unit 1 Lesson 5 States of Matter Changes of State 3. Evaporation – liquid becomes gas Add heat, speed up vibrations in particles Particles get enough energy that they ESCAPE from the surface! 4. Boiling–liquid becomes gas/vapor QUICKLY Happens throughout whole liquid, not just surface The TEMPERATURE at which this occurs is the boiling point Read and do page 80 Copyright © Houghton Mifflin Harcourt Publishing Company 11

Unit 1 Lesson 6 Changes of State How does evaporation differ from boiling? Which of these processes is represented here? Copyright © Houghton Mifflin Harcourt Publishing Company

Changes of State 5. Condensation – gas becomes liquid Unit 1 Lesson 5 States of Matter 5. Condensation – gas becomes liquid Gas is cooled, particles loose energy Particles stick together Read and do page 81 Copyright © Houghton Mifflin Harcourt Publishing Company 13

Changes of State 6. Sublimation – solid becomes gas Less common Unit 1 Lesson 5 States of Matter Changes of State 6. Sublimation – solid becomes gas Less common Ex. Ice in freezer, or dry ice Read and do page 82 and 83 7. Deposition – gas becomes solid Ex. Snowflakes! Copyright © Houghton Mifflin Harcourt Publishing Company 14

What happens when matter changes state? Unit 1 Lesson 6 Changes of State What happens when matter changes state? Where in this diagram do water particles gain energy from the environment? Where do they lose energy? Do page 77 – the whole page Copyright © Houghton Mifflin Harcourt Publishing Company

Good quiz questions! When matter changes from one state to another … …does its identity change? … does its mass change? … does its physical state change? … does its appearance change? Do page 84 (bottom) in class Do page 85 (bottom) in class