1. Define in your own words: element, compound, and mixture.
Copy and Answer the following questions:
Instructions: Write E in the blank if the material is heterogeneous or O if it is homogeneous.
Wood __________ Dirt __________
Lemonade __________ Sausage & mushroom pizza__________
Water __________ Air __________
Lucky Charms ®__________ Milk __________
Salt __________ Gold __________
Instructions: Classify each of the following as an element (E), a compound (C), or a mixture (M).
Gold __________ Air __________
Water __________ Carbon Dioxide (CO2) __________
Seawater __________ Silver __________
Sugar __________ Ice __________
A chocolate sundae __________ A Big Mac® __________

2. MATTER EQ: How do we describe and classify matter? &
What is the difference between a chemical and physical change?

3. Review: Pure Substance Mixture
Matter is anything that occupies space (volume) and has mass
Can describe matter as …
Pure Substance
Mixture
Element:
Composed of identical atoms
Remember monatomic, diatomic, & allotropes ?
Compound:
Composed of 2 or more elements in a fixed ratio
Mixture are two or more substances physically combined
Heterogeneous
Homogeneous

4. Can it be physically separated?
MATTER
yes no
Can it be physically separated?
MIXTURE
PURE SUBSTANCE
Is the composition uniform? no
yes
Can it be chemically decomposed? no
yes
Homogeneous Mixture
(solution)
Heterogeneous Mixture
Compound
Element

5. How do we describe Matter?
Physical and Chemical Properties

6. Physical Properties
Characteristics that can be observed without changing the identity.
EXAMPLES:
Texture
Color
Mass
Solubility
Melting/Boiling points
Volume
Density
State
conductivity

7. Chemical Properties
Characteristics that describe the ability of the substance to undergo changes in identity.
Describes how the substance reacts with others.
EXAMPLES:
Flammability
Combustibility
Reaction with oxygen
Reaction with other chemicals (acids)

8. Physical and Chemical Changes
What are the differences?

9. Physical Change
Changes the form of the substance WITHOUT changing its identity.
A change in size, shape, or state
EXAMPLES:
Freezing Evaporation Condensation
Boiling Dissolving Sublimation
Melting Crushing Vaporization

10. Chemical Change Changes the substance by changing the identity.
A changes to a new and different substance
Chemical Reaction:
Reactants  Products
Involves chemical energy
Endothermic: absorbs energy
Exothermic: releases energy
EXAMPLES:
Burning Reacting Rusting
Digesting Fermenting Souring

11. Evidence of a CHEMICAL CHANGE:
production of a gas (bubbles, odor)
Formation of a precipitate (insoluble solid from 2 liquids)
Observe energy
Evolution or absorption of heat (endo-/exo- thermic reactions)
Emission of light
Color change in reaction system