1. Matter and Atoms
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2. What is Matter?
Matter – a term used to describe anything that has mass and takes up space
Not matter
Light
Heat
Energy

6. Early Ideas Democritus
Universe made of empty space and tiny bits of stuff
Atom – Greek word meaning “can not divide”

7. Atom
Atom – a small particle that makes up most types of matter

8. Conservation of Matter
2,000 years pass
Lavoiser – showed that no change in mass during chemical reactions
Example – log burning

9. Proust
Proust – matter is made of small particles that behave in ways that can be predicted and measured

10. Dalton’s Models of an Atom
John Dalton – 1st model of an atom
All of the atoms in something are identical
Atoms of different elements are different from each other

11. Size of an Atom 1980’s – electron microscopes
Allowed Scientist to see an atom

12. Inside an Atom Nucleus – center of an atom
Contains protons and neutrons
Proton – particle with a positive charge (+)
Neutron – particle with no charge (0)
Most of mass

14. Inside an Atom
Electrons – particle inside an atom with a negative charge
Equal number of protons and electrons
Located in electron cloud