1. More about Matter
Use the information on these slides to check and improve your organization of matter.

2. Is Air matter? What are the two criteria for matter? Takes up space
Has mass

3. What is NOT Matter?
Energy!

4. What is the composition of matter?
Pure Substance
Mixture

5. What is a pure substance?
A pure substance has a definite composition (chemical formula).
The composition of a substance will have the same percent of elements no matter where the sample was obtained.
Water from the Cuyahoga River and water from the Pacific Ocean (once cleaned up) will have the same ratio of hydrogen to oxygen.
Oxygen here is the same as in Columbus

6. What is a pure substance?
A pure substance, by definition, is an element or a compound.
Water is a compound, and thus a pure substance.

7. Pure Substance
Pure Substance
Compound
Element

8. Element Atom What is an element?
a pure substance made of only one kind of atom
An atom is the smallest unit of an element that maintains the properties of that element.
Element
Atom

9. Elemental Samples Zinc, copper, lead, carbon, sulfur…
anything on the periodic table

10. What is a compound?
a substance that is made from the atoms of two or more elements that are chemically bonded
has a definite chemical formula
cannot be broken down any farther by
simple physical means
smallest amount of a compound with all the properties is a molecule

11. Compound Molecule What is a compound?
A molecule is the smallest unit of a compound.
Compound
Molecule

12. Examples of compounds? Carbon dioxide CO2 Water H2O Sugar C6H12O6
Oxygen O2
Table salt NaCl
1 molecule of table salt is the smallest amount that is still table salt. Can’t break it down any farther by physical means…

13. What is the composition of matter?
Pure Substance
Mixture

14. Mixture
A mixture is made up of two or more substances that are not chemically combined.
Mixtures can be separated by simple physical means.
e.g. sand and salt, salad

15. Mixtures
Two mixtures containing the same substances may not have the same proportions.
Example: not all salads have the same amount of tomatoes, but they are all salads

16. Water and Food Coloring Mixture
Two mixtures of the same substances may have different proportions.

17. Mixtures
Mixtures
Homogeneous
Heterogeneous

18. Homogeneous Mixture
Homogeneous mixtures are uniform in composition, i.e. particles are evenly spread throughout and you can’t see any differences
They have the same proportion of components throughout.
Examples:
- Salt water - Sugar water
- Air Carbonated water

19. Solution
A homogeneous mixture when two or more substances are evenly distributed in one another.

20. Alloy
A solid or liquid mixture of two or more metals (e.g. brass, bronze)
Is a solution, because particles are evenly spread

21. Homogeneous Mixture
Solution
Alloy

22. Heterogeneous Mixture
Heterogeneous mixtures are not uniform throughout; you can see differences
Molecules are not evenly spread
If the particles settle over time, it’s called a suspension (if they don’t settle, it’s called a colloid)

23. What is a suspension? A mixture in which particles settle over time.
Examples: Orange juice with pulp and muddy water

24. Heterogeneous Mixture
colloid
Suspension

25. Working backwards...4 examples
Matter
Pure substance
Mixture
homogeneous
heterogeneous
element
compound
suspension
solution
alloy
atom
molecule
brass
Italian salad
dressing
black coffee
gold

28. What is a colloid?
A heterogeneous mixture suspension where the particles are small enough not to settle.
May appear to be the same throughout but it is not!
Examples:
-Fog -Jello
-Paint -Smoke
-Whipped cream -Marshmallow

29. Tyndall Effect Sometimes the particles are too small to see.
Light does not pass through colloids because their particles scatter light.
This is called the Tyndall Effect.

30. What is an emulsion? A special case of a colloid
A mixture of two immiscible liquids (ones that usually don’t mix)
Examples: mayonnaise, butter, whole milk