1. Unit 5 Lesson 1 What Are Physical and Chemical Changes?
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2. Unit 5 Lesson 1 What Are Physical and Chemical Changes?
Florida Benchmark
SC.4.P.9.1 Identify some familiar changes in materials that result in other materials with different characteristics, such as decaying animal or plant matter, burning, rusting, and cooking.
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3. Physical Changes Are All Around
Unit 5 Lesson 1 What Are Physical and Chemical 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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4. Chemical Changes Are All Around
Unit 5 Lesson 1 What Are Physical and Chemical Changes?
Chemical Changes Are All Around
A chemical change occurs when one or more substances are changed into entirely new substances.
Rusting metal and rotting leaves are examples of chemical changes.
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5. Unit 5 Lesson 1 What Are Physical and Chemical Changes?
Chemical vs. Physical
Cutting an orange is an example of a physical change.
An orange decaying is an example of a chemical change.
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6. Chemical Changes at Home
Unit 5 Lesson 1 What Are Physical and Chemical Changes?
Chemical Changes at Home
There are four signs that a chemical change has occurred.
A release of gas or an odor can indicate a chemical change.
A color change can indicate a chemical change.
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7. Chemical Changes at Home
Unit 5 Lesson 1 What Are Physical and Chemical Changes?
Chemical Changes at Home
A change in temperature can indicate a chemical change.
The formation of a new substance can indicate a chemical change.
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8. Unit 5 Lesson 1 What Are Physical and Chemical Changes?
Making Pizza
When you make pizza, several physical and chemical changes occur.
Pushing and pulling the dough and cutting the vegetables are physical changes.
The action of the yeast and the baking of the pizza are chemical changes.
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