1. Classification of Matter

2. Element Pure substance
Made of same type of atoms
Cannot be separated into simpler substances by chemical or physical changes
always has same properties as another pure sample
Example: copper wire

3. Compound Made of two or more different elements chemically combined
Example: H2O
Follows Law of Definite Proportions
Elements making up the compound are combined in a definite proportion by mass
Percent composition of elements in the compound are always the same
% comp = mass of element x 100%
mass of compound

4. Practice Problem
In 100 g sample of water, there is 11.2 g of Hydrogen and 88.8 g of Oxygen, what is the percent composition of oxygen in water?

5. Chemical and physical properties of a compound differ from those of the elements that it is made up from
Water: liquid at room temperature; puts out fires
Hydrogen: gas at room temperature; flammable
Oxygen: gas at room temperature; flammable

6. 3. Mixtures consist of parts that have different properties
Consists of two or more substances that each retain their own individual properties
3 ways formed:
2 or more elements mixed together
Mixture of copper and nickel coins
A compound and element mixed together
2 or more compounds mixed together
Mixture of sugar and salt

7. Properties of Mixtures
Mixture retains properties of each of the different parts of the mixture
Composition of mixture varies
Not equal proportion of elements or compounds by mass in a mixture
Example: Bag of fruit snacks

8. Types of Mixtures Homogenous
sample from one part of mixture has the same composition as a sample from any other part of the mixture
Example: Ketchup, perfume, shampoo

9. Solutions Homogenous mixture 2 parts: Example: Salt water
Solute: substance that gets dissolved
Solvent: substance in which the solute gets dissolved
Example: Salt water
Salt = solute
Water = solvent

10. Heterogeneous
Sample of matter that has parts with different compositions
Throw salt on top of sugar – not equal composition throughout mixture
Example: italian dressing

11. Separating Mixtures Filtration Distillation Chromatography
Use porous barrier to separate a solid from a liquid
Distillation
Separates liquids with different boiling points
Chromatography
Separates different components as moves across the surface of another material
Crystallization
Formation of pure solid from a solution