1. Aim: How do we classify matter?
1) Two grams of potassium chloride are completely dissolved in a sample of water in a beaker. This solution is classified as
A) an element
B) a compound
C) a homogeneous mixture
D) a heterogeneous mixture
2Which formula represents a mixture?
A) C6H12O6(l)
B) C6H12O6(s)
C) LiCl(aq)
D) LiCl(s)
Warm Up:

2. Classifying Matter Pure Substance: contains only one type of matter.
Ex: pure water
Mixture: contains two or more types of matter.
Ex: pool water (contains water and chlorine)

3. Pure Substances
1. Elements: one type of atom that cannot be broken down by chemical means.
2. Compounds: two or more different types of atoms bonded together that can be broken down by chemical means.

4. Element or Compound?
element
element
compound

5. Elements Can be either atoms or molecules.
All elements are located on the Periodic Table of Elements.
Examples of elements that are atoms:
Na, K, S, C, Au, Ag, Kr, etc.
Examples of elements that are molecules:
O2, H2, Cl2, N2
** Please note that both only contain one type of atom!

6. The elements that are molecules are called diatomic elements.
How am I supposed to know which elements are atoms and which are molecules??
That’s easy!
The elements that are molecules are called diatomic elements.
You need to memorize the words H O F Br I N Cl
Hydrogen (H2) Bromine (Br2)
Oxygen (O2) Iodine (I2)
Fluorine (F2) Nitrogen (N2)
Chlorine (Cl2)

7. Compounds Compounds are formed when 2 or more different atoms join.
Compounds can be broken down into elements by chemical reactions called decomposition.
Common compounds to know:
NaCl sodium chloride (salt)
H2O water
NH3 ammonia
CH4 methane
CO2 carbon dioxide

8. Mixtures A mixture is a PHYSICAL blend of two or more substances.
Since they are only physically mixed, mixtures can be separated based on certain properties.
More on separating mixtures later…

9. Examples of Common Mixtures
System
Example
Gas-Gas
Air
Liquid-Gas
Water vapor in air
Gas-Liquid
Soda, shaving cream
Liquid-Liquid
Vinegar
Solid-Liquid
Salt water
Solid-Solid
Sterling Silver

10. Classifying Mixtures Mixtures can be classified as HOMOGENEOUS
HETEROGENEOUS OR

11. Homogeneous Mixtures
a mixture in which the components of the mixture are uniform throughout.
Salt water and iced tea are good examples of homogeneous mixtures.
Also, the colors green, purple, etc. are mixtures.

12. Heterogeneous Mixtures
Heterogeneous mixtures do not have uniform composition.
A good example of a heterogeneous mixture is a salad.

13. Heterogeneous or Homogeneous?

14. Practice
Substance, element, atom

15. Practice
Mixture, compounds, molecules

16. Practice
Substance, elements, molecules

17. Practice
Mixture, elements, atoms

18. Practice
Mixture, elements, atoms and molecules

19. Practice
Substance, compound, molecules

20. Aim: How do we separate mixtures?
You are given the following mixture how would you separate out each of the components? Which properties would you focus on?

21. Properties of Matter
Physical properties can be observed or measured with out changing the chemical composition (hardness, phase, color, volatility etc.)
Chemical properties are related to a substances ability to undergo chemical reactions.

22. Physical vs Chemical Properties
Physcial Properties (characteristics)
Chemical Properties (characteristics)
Mass
Corrosive
Volume
Flammable
Temperature
Combustable
Density
Oxidizer
Boiling Point
Reducer
Melting Point
Reacts
Hardness
Forms new products with …
Color
Stable
Phase (solid, Liquid Gas)
Unstable
Solubility
Anything that describes how it reacts

23. Reference Table - S Properties of Elements
Melting Point, Boiling Point and Density are all physical properties.
Examples:
What is the boiling point of helium in °C?
What volume would a 0.5 g sample of Oxygen occupy at STP?
In what phase would Calcium be found at 1000 K?

24. Separating Mixtures
Separating mixtures can be done based on such properties as
1) boiling point,
2) magnetism,
3) solubility,etc.

25. Distillation
Distillation separates mixtures of liquids by boiling point.

26. Chromatography
Chromatography is based on different rates of migration of the components.

27. Filtration