2. Elements:
A pure substance containing only one kind of __atom____.
An element is always uniform all the way through (homogeneous).
An element __cannot___ be separated into simpler materials (except during nuclear reactions).
Over 100 existing elements are listed and classified on the _Periodic Table_.

3. Compounds:
A pure substance containing two or more kinds of __atoms__.
The atoms are ___chemically___ combined in some way. Often times (but not always) they come together to form groups of atoms called molecules.
A compound is always homogeneous (uniform).
Compounds ___cannot___ be separated by physical means. Separating a compound requires a chemical reaction.
The properties of a compound are usually different than the properties of the elements it contains.

4. MIXTURES
A physical blend of 2 or more substances. Heterogeneous: not uniform in composition oil and water are immiscible. Not the same throughout. Homogeneous: uniform throughout Miscible solutions such as salt water

5. Mixtures:
Two or more __elements___ or ____compounds__ NOT chemically combined.
No reaction between substances.
Mixtures can be uniform (called __homogeneous___) and are known as solutions.
Mixtures can also be non-uniform (called ____heterogeneous____) colloids and suspensions.
Mixtures can be separated into their components by chemical or physical means Filtration, magnetic.
The properties of a mixture are similar to the properties of its components.

6. SOLUTION
HOMOGENEOUS MIXTURES: not matter where you take a sample from it will have the same composition as any other portion. PHASE: any part of a system w/ uniform composition and properties. So a homogeneous mixture contains only 1 phase What about heterogeneous mixtures then?

7. colloids

8. Homogeneous mixtures: air, blood plasma, saturated sugar water metal alloys
Heterogeneous mixtures: rocks, oil and water, soup, pizza

9. Separation of Mixtures
Tap Water can be separated into pure water and other components by distillation.
Some simple methods of separating mixtures?

10. How would you separate….
Sawdust from sand?
Add water, sawdust floats and sand sinks
2. Sand from salt?
Add water, salt dissolves and sand doesn’t. Pour solution onto cloth for sand. Let the solution evaporate to collect salt.

12. States of Matter
PHYSICAL STATES

13. States of Matter
Solids: Definite Shape and Volume. Particles packed tightly together. Liquids: Matter that flows, (viscosity) has a fixed volume and takes the shape of the container. Gas: Matter that takes both the shape (diffuse) and volume of its container.

14. Gas or Vapor
Gas: substances that exist in the gaseous state at room temp. Air is a mixture of Nitrogen and Oxygen. Vapor: a substance that although in the gaseous state is generally a liquid or solid at room temp. Steam is the gaseous form of water.

15. PHYSICAL and CHEMICAL PROPERTIES
PHYSICAL: Boiling pt, Melting pt., Shininess, Volatility, Color, Taste, Odor, Softness, Hardness, Slipperiness, Ductility, Malleable, Electrical Conductivity, Dissolve in Water, and Density
CHEMICAL: Burns in air, Explodes, Tarnishes, Reacts w/ metals, Reacts w/ acids, Reacts w/ water, Decomposes when heated, Reacts w/ nonmetals and is toxic
Ability to change to form a new substance

16. Physical and Chemical Changes
PHYSICAL: A change in which the atoms or molecules in a substance stay the same. (Boil, Freeze, Dissolve, Melt, Break, Condense, Crush, Crack) CHEMICAL: A change that affects the type of molecules or atoms in a substance.

17. CHEMICAL REACTIONS
REACTANTS: Starting Substances PRODUCTS: New Substances Iron + Sulfur  Iron Sulfide
yields
REACTANTS
PRODUCTS

18. Define matter in a complete sentence.
Write questions in your notebook, then answer.
Define matter in a complete sentence.
List the three common states (phases) of matter:
Which state of matter has:
no definite shape, nor definite volume
no definite shape, but definite volume
definite shape and definite volume
How do you change a solid into a liquid? Give an example.
How do you change a gas into a liquid? Give an example.
Use your answers from the two problems above to explain why phase changes are "reversible".
List three physical properties of matter.
When matter undergoes a physical change, has its physical properties changed? Give an example.
What do we mean when we speak of a substance's "composition"? Use your prior knowledge of atoms, molecules, elements, compounds and mixtures.
When matter undergoes a physical change, does the composition of the matter change? Give an example.
List two chemical properties of matter.
After a chemical change has the physical and chemical properties of a substance changed? Give an example.
Give two examples of common items that use chemical change.

19. After recording in your notebook, tell whether the following are chemical or physical changes:
mixing salt and pepper freezing water
cutting a marshmallow melting sugar
toasting a marshmallow iron rusting
adding chocolate syrup to milk burning wood
breaking glass boiling water
magnetizing a piece of steel melting wax
hammering gold into a thin foil burning wax
pouring molten gold into a mold
dissolving sugar in water

20. Kinetic Theory of Matter
This theory explains how atoms/molecules behave in the different phases of matter and will be needed again when we discuss gas laws