1. Unit 7 Lesson 4 What Are the States of Water?
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2. Solids, Liquids, and Gases
Unit 7 Lesson 4 What Are the States of Water?
Solids, Liquids, and Gases
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3. Solids, Liquids, and Gases
Unit 7 Lesson 4 What Are the States of Water?
Solids, Liquids, and Gases
Matter exists in different forms.
Solids, liquids, and gases are three states of matter.
Most matter on Earth is classified as one of these forms.
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4. Solids, Liquids, and Gases
Unit 7 Lesson 4 What Are the States of Water?
Solids, Liquids, and Gases
A solid has a definite volume and shape.
Your desk, book, pencil, and chair are all solids.
Solids stay solid unless something, such as heat, changes them.
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5. Solids, Liquids, and Gases
Unit 7 Lesson 4 What Are the States of Water?
Solids, Liquids, and Gases
A liquid has a definite volume but not a definite shape.
Water, shampoo, and fruit juice are liquids.
A liquid takes the shape of its container.
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6. Solids, Liquids, and Gases
Unit 7 Lesson 4 What Are the States of Water?
Solids, Liquids, and Gases
A gas doesn’t have a definite volume or shape.
Air is an example of a gas.
A gas expands to take up all the space in a container.
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7. Unit 7 Lesson 4 What Are the States of Water?
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8. Unit 7 Lesson 4 What Are the States of Water?
Water’s Forms
Solid
Water in the solid state has a definite volume and shape.
The particles in solids are close together. They are moving but stay in the same spot.
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9. Unit 7 Lesson 4 What Are the States of Water?
Water’s Forms
Liquid
Water in the liquid state has a definite volume but not a definite shape.
Generally, the particles in a liquid are a bit farther apart than in a solid. They move around more, too. The particles slide past each other.
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10. Unit 7 Lesson 4 What Are the States of Water?
Water’s Forms
Gas
When water is a gas, it is called water vapor. It doesn’t have a definite volume or shape.
Particles in a gas are far apart. They are much farther apart than the particles in a liquid. They move quickly in all directions.
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11. Unit 7 Lesson 4 What Are the States of Water?
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12. Unit 7 Lesson 4 What Are the States of Water?
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13. Water’s Forms Which is a solid? Which is a liquid? Which is a gas?
Unit 7 Lesson 4 What Are the States of Water?
Water’s Forms
Which is a solid? Which is a liquid? Which is a gas?
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14. Water Changes Form Freezing
Unit 7 Lesson 4 What Are the States of Water?
Water Changes Form
Freezing
A change of state occurs when matter changes from one state to another.
As heat energy is removed from water, the particles slow down, get closer together, and lock into place. Water freezes.
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15. Water Changes Form Melting
Unit 7 Lesson 4 What Are the States of Water?
Water Changes Form
Melting
Adding heat energy causes ice to melt. Water melts when it changes from a solid to a liquid.
During melting, particles speed up until they overcome the attractions that hold them in place.
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16. Water Changes Form Evaporation
Unit 7 Lesson 4 What Are the States of Water?
Water Changes Form
Evaporation
Evaporation is the process by which a liquid changes into a gas.
When heat energy is added to liquid water, its particles speed up.
Particles that gain enough energy enter the air as water vapor.
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17. Water Changes Form Condensation
Unit 7 Lesson 4 What Are the States of Water?
Water Changes Form
Condensation
When heat energy is removed from a gas, its particles slow down and clump together.
Condensation is the process by which a gas changes into a liquid.
Clouds form when water vapor condenses on particles of dust in the air.
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18. Unit 7 Lesson 4 What Are the States of Water?
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