1. Unit 9 Lesson 2 What Are the States of Matter?
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2. Unit 9 Lesson 2 What Are the States of Matter?
What’s the State?
There are three common states of matter: solid, liquid, and gas.
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3. Unit 9 Lesson 2 What Are the States of Matter?
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4. Unit 9 Lesson 2 What Are the States of Matter?
What’s the State?
A solid is matter that takes up a definite amount of space. Solids also have a definite shape.
Your science book is a solid. Ice is also a solid.
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5. Unit 9 Lesson 2 What Are the States of Matter?
What’s the State?
A liquid is matter that takes up a definite amount of space but does not have a definite shape.
Liquids take the shape of their containers.
Drinking water is a liquid.
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6. Unit 9 Lesson 2 What Are the States of Matter?
What’s the State?
A gas is matter that does not take up a definite amount of space and does not have a definite shape.
The air around you is a gas.
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7. Cool! It’s Freezing! When water cools, it loses energy.
Unit 9 Lesson 2 What Are the States of Matter?
Cool! It’s Freezing!
When water cools, it loses energy.
When it is cooled enough, it freezes.
Freezing is the change of state from liquid to solid.
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8. Unit 9 Lesson 2 What Are the States of Matter?
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9. Cool! It’s Freezing! Below the freezing temperature, water is a solid.
Unit 9 Lesson 2 What Are the States of Matter?
Cool! It’s Freezing!
Below the freezing temperature, water is a solid.
Hail, ice on a lake, and a snowball are examples of solids. Each of these examples is water frozen into a solid.
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10. Unit 9 Lesson 2 What Are the States of Matter?
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11. Unit 9 Lesson 2 What Are the States of Matter?
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12. Unit 9 Lesson 2 What Are the States of Matter?
Just Add Heat!
When water is heated, it gains energy. If ice is heated enough, it melts.
Melting is the change of state from a solid to a liquid. Melting is the opposite of freezing.
Water melts above 0 °C (32 °F) and freezes below 0 °C (32 °F).
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13. Unit 9 Lesson 2 What Are the States of Matter?
Just Add Heat!
If enough energy is added to water, it boils and changes to a gas.
Water boils at 100 °C (212 °F).
Water in the form of gas in called water vapor. Water vapor is invisible.
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14. Unit 9 Lesson 2 What Are the States of Matter?
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15. Unit 9 Lesson 2 What Are the States of Matter?
Now You See It …
Liquid water can change to a gas without boiling. This process is called evaporation.
Water evaporates from puddles on a warm day.
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16. Now You See It … What happened to the water?
Unit 9 Lesson 2 What Are the States of Matter?
Now You See It …
What happened to the water?
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17. Unit 9 Lesson 2 What Are the States of Matter?
Now You See It …
A gas can change back to a liquid in a process called condensation.
When water vapor loses energy, such as on a cold window pane, it changes to a liquid.
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18. Unit 9 Lesson 2 What Are the States of Matter?
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19. Unit 9 Lesson 2 What Are the States of Matter?
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20. Unit 9 Lesson 2 What Are the States of Matter?
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