Here are the answers: 1) Cutting Grass - Physical 2) Burning Toast - Chemical 3) Wadding up Homework - Physical 4) Ice Cream Melting - Physical 5) Frying an Egg - Chemical 6) Gasoline Combustion - Chemical 7) Sweat Evaporating - Physical

1. Ch. 20
Properties & Changes in Matter

2. Brain warmer:
 Looking at the picture, what physical changes
are taking place?

3. Today’s Essential Questions:
 1) What are chemical properties?
 2) What are the differences between physical and
chemical changes?

4. Goals for today:
 Goal #1- Recognize and list chemical properties by
viewing power point and note-taking.
 Goal #2- Differentiate and classify physical and
chemical changes through an on-line lab.

5. Review of Physical Properties
 Color & Shape
 Length & Mass
 Volume & Density
 Melting & Boiling Point
 States of Matter
 Attraction to magnets
1) A change in state of matter
produces a physical change.

6. Chemical Properties
 2) What is a chemical property?
Any characteristic that gives a substance the ability to
undergo a change that results in a NEW substance.
 3) What is a chemical change?
A change in the identity of a substance due to the
chemical properties of a substance.

7. Overview of Chemical Properties
 Flammability
 Ability to react with:
 Oxygen
 Electricity
 Light
 Water
 Heat
 Vinegar Two substances are mixed
to produce…
 Bleach and MORE

8. Chemical Property-Flammability
 4) Flammability- the ability of something to catch
fire or produce flames
Example: When wood is set on fire. Eventually the
wood becomes ash, noting a chemical change.

9. Chemical Property:
Ability to React with Oxygen
 5) Ability to React with Oxygen
•Example-Fruit, such
as apples, will turn
brown when exposed
to oxygen. This is a
chemical reaction.

10. Chemical Property:
Ability to React with
 6) Electricity
 7) Light
 8) Water
LIGHT
 9) Heat
 10) Vinegar
 11) Bleach
HEAT

11. How to tell:
Is it a physical or chemical change?
Physical Chemical
•Changes shape or size •Makes new substance
•Dissolves •It burns
•Changes phase or state of •Temperature changes
matter without heating or cooling
•Reversible •It bubbles (or makes a gas)
•It can change color
•IRREVERSIBLE

12. Check for Understanding
Are the following examples of physical or chemical
changes?
1) Cutting Grass
2) Burning Toast
3) Wadding up Homework
4) Ice Cream Melting
5) Frying an Egg
6) Gasoline Combustion
7) Sweat Evaporating