1. 2.3: What are pure substances and how are they classified?

2. Both devices use properties to separate mixtures of matter into
A. A dip net is a traditional Aboriginal tool designed to separate big fish from smaller fish or water.
B. A device used to analyze & identify the types of matter in a sample from a crime scene.
Both devices use properties to separate mixtures of matter into
their parts!

3. Pure substances are elements & compounds
Matter is usually classified by its physical & chemical properties.
Early scientists grouped matter on how they could break it apart.
Matter that could be seperated into parts using differences in physical properties was classified as a mixture.
Matter that is not a mixture is a pure substance.

4. Classifying Matter

5. Pure Substances
Pure Substance – matter that contains only one type of particle, so it cannot be sepeated into parts physically.
Examples: table sugar (sucrose), oxygen, pure water, copper, aluminum.
Each part of a pure substance has the same properties however, the kinds of particles of one pure substance is different from the particles of other pure substances.

6. Pure Substances

7. Compounds & Elements There are two types of pure substances
Compounds – a pure substance made up of two or more elements that are chemically combined. They can be broken down into elements again by chemical reactions.
Element – a pure substance made up of one type of particle that cannot be broken down into simpler parts by chemical means.

8. Compounds can be broken down & Elements can’t!
Energy can be used to un-combine the compound into the two individual elements again.
The elements cannot be un-combined any further.

9. The Classification of Matter

11. Answers

12. Elements include metals & non-metals
One way elements can be classified is to group them into two categories:
Metals – elements that are commonly solid at room temperature, shiny, malleable, ductile, & good conductors
Non-Metals – elements that can be solid, liquid, or gas at room temperature, dull, brittle, not ductile, & poor conductors

13. Classifying metals & non-metals

14. Examples of metals & non-metals

16. Answers: