1. Particle Theory of Matter (4 Principles)
1. All matter is made of tiny particles
2. All particles of a pure substance are the same. Different substances are made of different particles.

2. 3. Particles are always moving
3. Particles are always moving. The more energy they have the faster they move.
4. There are attractive forces between particles. These forces are stronger when the particles are closer together.

3. Pure substance- A substance that contains only one type of particle
Pure Substances vs. Mixtures
Pure substance- A substance that contains only one type of particle
Mixture- A grouping of more than one type of substance

4. Pure Substances Compound A molecule that contains two or more
different elements
Element A pure substance that can not be broken down into a simpler substance
Molecule
The combination of two or more atoms in a compound or element

5. Mixtures Heterogeneous Mixture A mixture in which the different
components are visible and they
can be separated physically
Homogeneous Mixture (Solution)
A mixture in which the different components
are not visible

6. Hints Elements in Substance Type of substance Description
Element A alone
Pure substance (element)
Only Element A is visible
Elements A and B
Pure substance (compound)
The compound may have completely different properties from each of the elements. The elements are chemically combined.
Mixture (homogeneous)
The solution may look very similar to one of the elements, as particles of the other substance are hidden within it
Mixture (heterogeneous)
Particles of each element can be seen separately