1. Warmup – States of Matter
List one property that solids and gases share.
List three properties they do not share.
3. Describe the movement of particles in a liquid.

2. sample of matter Can it be separated by physical means? YES NO
MIXTURE PURE SUBSTANCE
(> 1 kind of atom and/or compound) (only 1 kind of atom OR compound)

3. Let’s focus on mixtures first
Is the composition uniform?
YES NO
HOMOGENEOUS HETEROGENEOUS
e.g e.g.

4. Now let’s look at pure substances
Can it be decomposed by ordinary, chemical means?
YES NO
COMPOUND ELEMENT
(> 1 kind of atom) (only 1 kind of atom)
e.g e.g.

5. Let’s turn to elements (only 1 kind of atom) One atom? Monatomic
Two atoms? Diatomic
Three atoms? Triatomic
More than one form?
Allotropic
O: O2, O3
C: graphite, diamond,
buckyballs, graphene (single layer of C atoms)

6. Mixtures vs Pure Substances Compounds vs Elements

7. Elements and Compounds
simplest form of matter – contain only 1 kind of atom
cannot be broken down further by chemical means
e.g. C, N2, O2, H2
Compound:
made up of 2 or more elements
can be broken down chemically
e.g. H2O, NH3, CO2

8. Elements and Compounds
Example of the breakdown of a compound  its elements
cane sugar C12H22O11
chemical
change
C H2O
(element) (compound)
H O2
(element) (element)

9. Elements and Compounds
Note:
In general, chemical and physical properties of elements DIFFER from those of the compounds they make.
e.g. H2 and O2 vs. H2O

10. Physical Separation of Mixtures
Process Property exploited
Filtration solubility
Evaporation boiling point
Centrifuge density
Decant density
Magnetism magnetism
Distillation boiling point
Sifting size or shape
Chromatography size/polarity/charge
Crystallization solubility

11. Filtration vs Decanting
Filter
Decant
Substance must be dissolved or suspended in water
Denser solid drops to bottom of beaker, liquid can then be poured off the top

12. Distillation

13. Chromatography

14. Fractional Crystallization e. g
Fractional Crystallization e.g. separation of radium chloride from barium chloride by Marie and Pierre Curie