1. Chapter 1, Unit 1: Properties of Matter
Wednesday, September 5, 2012
Chapter 1, Unit 1: Properties of Matter

2. Something to think about….
What is the difference between physical and chemical properties of matter?
Distinguish between an element and a compound.
How can you determine whether or not a chemical reaction has occurred?
What happens to chemical bonds during a chemical reaction?

3. What do ya know?
Classify the following as chemical or physical changes:
Ice cream melting?
Physical
Sugar dissolving in water?
Chemical
Candle burning?
Bathroom mirror fogging as someone showers?
Milk turning sour?

4. Physical and Chemical Properties
Observed without changing into something else.
Color
Texture
Shape
Chemical
Observed by changing into something else.
Dissolvability
Burning
Rusting

5. Elements, Compounds, & Mixtures
Cannot be broken down into any other substance by physical or chemical means
Examples
Oxygen
Tin
Calcium
Symbol
1 or 2 letters that represent an element.
H-Hydrogen, Ca-Calcium, O-Oxygen
Compounds
Made up of two (2) or more elements that are chemically bound together in a set ratio.
Example
Water
2 Hydrogen, 1 oxygen

6. Oxygen

7. Elements, Compounds, & Mixtures cont’d.
Formula
Every compound is represented by a formula.
A formula shows the ratio of elements in the compound.
Water
H2O
Mixtures
Consists of two or more substances in the same place that are NOT chemically combined.
Parts of a mixture may be in varying ratios.
Example
Salads

8. Changes in Matter Physical Chemical
Alters the form or appearance of a material but does not convert the material into a new substance.
Chemical
A change in matter that forms one or more new substances.
Chemical Reaction
The key characteristic of a chemical reaction is the production of new materials that are chemically different from the starting materials.

9. Reading Chemical Equations
Short, simple way to describe a chemical reaction, using symbols and formulas instead of words.
Example
C + 2OCO2
Reactants
Substances you start with in a chemical reaction.
Products
The substances at the end of the reaction.

10. Chemical Reactions
When you observe a chemical change, you are watching the combined effect of countless changes involving tiny particles.
Atom
The smallest particle of an element.
Molecule
Made of 2 or more atoms
Chemical Bond
Force that holds atoms together.
During a chemical reaction, chemical bonds are either formed or broken apart.

11. Something to think about….
What is the difference between physical and chemical properties?
Physical characteristics that are observed without changing into something else; chemical properties are observed when changing into a whole new substance.
Distinguish between an element and a compound.
An element cannot be broken down into any other substance by physical or chemical means; a compound is made of two or more elements combined by a set ratio.
How can you determine whether or not a chemical reaction has occurred?
Whether or not there is a new substance formed or the physical appearance is altered.
What happens to chemical bonds during a chemical reaction?
They are either formed or broken apart.