1. What are Chemical Changes?
Grade 3
Chapter 3 Lesson 3
Mrs. Dira, Period D

2. Standard/Objective
Standard: 3PS1.g – Students know that when two or more substances are combined, a new substance may be formed with properties that are different from those of the original materials.
Objective: Students will see how changes in matter called chemical changes can produce new kinds of matter.

3. Vocabulary
Chemical change- one kind of matter changes into a different kind of matter.
Physical change- one kind of matter changes, but does not create a different kind of matter.
Mixing- combining items together

4. A) Forming Different Materials
A chemical change is when one kind of matter changes into a different kind of matter.
Chemical changes cannot be changed back to the original kind of matter.
Chemical changes create new kinds of matter.
Examples: baking bread, fireworks, rusty chain, campfire, burning a candle

5. B) Mixing Matter/Two Kinds of Changes
When some things combine and keep their original properties, this is a physical change.
Example: trail mix, salad
When some things combine and produce bubbles or new matter, this is a chemical change.
Example: vinegar and baking soda make carbon dioxide gas

6. C) Using Chemical Changes
We use chemical changes every day.
Nutrition-when you eat and when your body uses the material for energy and growth.
Transportation- gas burns in a car’s engine
Cleaning- chemicals break down stains
Food- milk turning into cheese
Medicine- tablets form bubbles in water for stomachaches
Electricity- chemicals combine inside batteries

7. Example How can matter change?
Hypothesis: I think _______________________will happen if we combine the materials together.
Materials- safety goggles, small measuring cup, plastic cup and spoon, glue, food coloring, and borax solution
Procedure:
1) Put 30 mL of glue into a cup. You can add food coloring
2) Add 15 mL of borax solution. Stir.
3) Observe the properties of the new substance.
Record observations. Collect your data in a chart.
How the Substances Changed
Properties of Substances Before Change
Properties of Substances After Change
Observations

8. Check for Understanding
Explain Your Results
1) Analyze your data. Tell if a newly formed substance can have different properties from those of the original materials. Tell how your data supports your conclusion.
2) Classify the changes. Was it a physical or a chemical change? How do you know?