1. Unit 8 Lesson 1 What Are Some Physical Changes?
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2. Physical Changes Are All Around
Unit 8 Lesson 1 What Are Some Physical Changes?
Physical Changes Are All Around
Copyright © Houghton Mifflin Harcourt Publishing Company

3. Physical Changes Are All Around
Unit 8 Lesson 1 What Are Some Physical Changes?
Physical Changes Are All Around
Copyright © Houghton Mifflin Harcourt Publishing Company

4. Physical Changes Are All Around
Unit 8 Lesson 1 What Are Some Physical Changes?
Physical Changes Are All Around
Copyright © Houghton Mifflin Harcourt Publishing Company

5. Physical Changes Are All Around
Unit 8 Lesson 1 What Are Some Physical Changes?
Physical Changes Are All Around
A physical change is a change in which a new substance is not formed.
Changing size and shape are physical changes.
Changing a physical property, such as size, shape, texture, or mass, is a physical change.
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6. Physical Changes Are All Around
Unit 8 Lesson 1 What Are Some Physical Changes?
Physical Changes Are All Around
Copyright © Houghton Mifflin Harcourt Publishing Company

7. Physical Changes Are All Around
Unit 8 Lesson 1 What Are Some Physical Changes?
Physical Changes Are All Around
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8. So Different, Yet the Same
Unit 8 Lesson 1 What Are Some Physical Changes?
So Different, Yet the Same
A change in state is a physical change that takes place when heat energy is added or removed from matter.
Melting is a change in state from a solid to a liquid.
Heat energy is added to a solid, causing it to melt.
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9. So Different, Yet the Same
Unit 8 Lesson 1 What Are Some Physical Changes?
So Different, Yet the Same
Evaporation is a change in state from a liquid to a gas.
Heat energy is added to a liquid, making it evaporate.
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10. So Different, Yet the Same
Unit 8 Lesson 1 What Are Some Physical Changes?
So Different, Yet the Same
Freezing is a change in state from a liquid to a solid
Heat energy is removed from the liquids, making it freeze.
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11. So Different, Yet the Same
Unit 8 Lesson 1 What Are Some Physical Changes?
So Different, Yet the Same
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12. Mix It Up! Unit 8 Lesson 1 What Are Some Physical Changes?
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13. Unit 8 Lesson 1 What Are Some Physical Changes?
Mix It Up!
A mixture is a combination of two or more substances that keep their identities.
Putting sand and water together does not change their physical properties. Sand is still sand. Water is still water.
Salad, air, and coins in a piggy bank are
all examples of mixtures.
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14. Unit 8 Lesson 1 What Are Some Physical Changes?
Mix It Up!
A solution is a mixture in which the substances are evenly mixed.
Some metals are a type of mixture. To make some rings, different metals are melted together, evenly mixed, and poured into a mold to cool and harden together.
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15. Unit 8 Lesson 1 What Are Some Physical Changes?
Mix It Up!
A solvent is the larger part of a solution that dissolves the other substances.
A solute is a substance that dissolves in a solvent.
Solutes are the smaller part of a solution.
Sea water is a solution. Water acts as the solvent and salts act as the solutes.
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16. Mix It Up! Unit 8 Lesson 1 What Are Some Physical Changes?
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17. Mix It Up! Unit 8 Lesson 1 What Are Some Physical Changes?
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18. Unit 8 Lesson 1 What Are Some Physical Changes?
Clean Up an Oily Mess
Oil is something that will not dissolve in water. Oil floats on top of water.
Water alone cannot clean up an oily mess. Detergent needs to be added.
Sometimes oil spills into our oceans and causes a lot of damage.
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19. Unit 8 Lesson 1 What Are Some Physical Changes?
Clean Up an Oily Mess
Detergent particles form bonds with water particles and reduce their ability to bond to each other.
Detergent particles also like to form bonds with oil particles.
Detergents and water work together to break up oil into smaller particles that can be washed away.
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20. Unit 8 Lesson 1 What Are Some Physical Changes?
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21. Unit 8 Lesson 1 What Are Some Physical Changes?
Clean Up an Oily Mess
To help clean animals from the effects of an oil spill, people use dishwashing detergent.
Detergent causes a physical change in the water particles and allows the oil to be washed away from bird feathers or animal fur.
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22. Unit 8 Lesson 1 What Are Some Physical Changes?
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