1. Physical Science Chapter 1.1
Describing Matter
Physical Science Chapter 1.1

2. Chemistry
Chemistry is the study of the properties of matter and how matter changes.
Brainstorm: What is matter?

3. Definition of Matter
Matter is the substance of which a physical object is composed

4. Properties of Matter
Hardness
Brainstorm:

5. More about Matter Matter is made up of elements. Analogy
bricks:buildings::elements:matter
An element is a substance that cannot be broken down into any other substances by chemical or physical means.

6. Elements Elements are made up of atoms Each element has its own symbol
Ex. The symbol for hydrogen is H.
Elements can exist in an uncombined or a combined form.
A compound is a substance made of two or more element chemically combined in a specific ratio
A formula is a combination of symbols that shows the ratio of elements in a compound
Example: CO2, carbon dioxide gas

7. Mixtures
A mixture is made from two or more substances-elements, compounds or both-that are together in the same place, but are not chemically combined into a new substance
Ex: a mixture of water and salt
Mixtures differ from compounds in two ways:
1. the substances in a mixture keep their individual properties
2. the parts of a mixture are not necessarily present in specific ratios

8. Changes in Matter
Physical Change vs. Chemical Change

9. Physical Change Changes in matter that do not produce a new substance
Alters the form or appearance of a material, but does not convert the material into new substances
Example: Chopping wood, changes in state

10. Chemical Change A change in matter that produces a new substance
Can also be called a chemical reaction
The new substances are made of the same elements as the original substances, but the atoms are rearranged in new combinations
Elements may combine to form compounds
Table Salt, NaCl
Compounds may be broken down into elements or other compounds
Burning paper

11. Vocabulary Chemistry Element Atom Symbol Compound Formula Mixture
Physical change
Chemical change
Chemical reaction

12. Questions
1. Name several properties of matter that help you identify an unknown substance.
What substances are the building blocks of matter?
Explain the difference between a physical change and a chemical change.
How does a chemical formula differ from a symbol?