1. Topic 2
Changes in Matter

2. Properties of Matter Physical Properties Chemical Properties
Are used to describe a substance
Chemical Properties
Describe how a substance interacts with other substances. Chemical properties are only observable when a chemical change occurs.
physical and chemical properties

3. Properties of Matter
Physical Properties

4. Physical Properties Qualitative Property Quantitative Property
A characteristic of a substance that can be described but might not be measured (a quality)
Quantitative Property
A characteristic of a substance that can be measured numerically (a quantity)

5. Changes in Matter Physical Changes Chemical Changes
A substance changes form but not chemical composition
Chemical Changes
Causes one or more new substances to be formed. It may be impossible to reverse.

6. Properties of Matter
Physical Changes

7. Properties of Matter Chemical Changes Reacts with water
Reacts with air
Reacts with pure oxygen
Reacts with acids
Reacts with other pure substances
Toxicity
Stability
Combustibility

8. Chemical change song

9. Identifying Physical and Chemical Changes
Look at the following pictures and document whether you think each is an example of a physical or chemical change.

10. Physical or Chemical Change?
It is difficult to determine whether changes are physical or chemical.
The following chart will help you decide whether a chemical change has occurred.
In order to be completely sure, chemical analysis in a lab must take place.