1. Warm Up
1. A small amount of a strong smelling sulfur compound is dissolved in natural gas to give gas a detectable odor. Which substance is the solvent?
2. True or False: A mixture has a set ratio of components.
3. Carbon dioxide is a gas at room temperature, but the element carbon is a solid. How can these two substances be so different?

2. Elements
A substance that cannot be separated or broken down into simpler substances.
Pure substance – only has one type of particle (atoms).
Elements are found on the periodic table
111 elements known

3. Elements
Every atom in a piece of gold is the same, no matter where it is found.
Every atom of iron is the same
spoon, steel rod, meteorite

4. I can describe the characteristics of elements, and give examples.

5. Properties of Elements
Characteristic properties – do not depend on the amt. of the element present.
Boiling point, melting pt., density, reactivity with acid, color, hardness, flammability
Can be used to identify elements

6. Properties of Elements
Identified by their physical and chemical properties
Categorized by similar properties
Metals, nonmetals, or metalloids

7. Classifying Elements Metals
Shiny, conduct heat and electricity, malleable, ductile
All are solid except mercury
Examples: copper (Cu), tin (Sn), lead (Pb), iron (Fe), gold (Au), mercury (Hg)

8. Can be solid, liquid, or gas
Classifying Elements
2. Nonmetals
Opposite of metals
dull, poor conductors heat and electricity, brittle, not malleable, not ductile
Can be solid, liquid, or gas
Examples: sulfur (S), iodine (I), neon (Ne), chlorine (Cl), oxygen (O), hydrogen (H)

9. Properties of both metals and nonmetals
Classifying elements
3. Metalloids
Properties of both metals and nonmetals
Semi-conductors
Some shiny, some dull, somewhat malleable and ductile, some conduct heat and electricity
Solids
Examples: boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te)

10. I can distinguish between metals, nonmetals, and metalloids.

11. Substances
Matter that has the same composition and properties throughout is called a substance.
When different elements combine, other substances are formed.

12. Substances Contains only one particle Can exist in 3 states of matter
Can be elements or compounds
Picture from

13. Compounds
A compound is a substance whose smallest unit is made up of atoms of more than one element bonded together.
Compounds often have properties that are different from the elements that make them up.
Examples: Water, salt, sugar

14. Compounds Have Formulas
H20 is the chemical formula for water, and H2O2 is the formula for hydrogen peroxide.
The formula tells you which elements make up a compound as well as how many atoms of each element are present.

15. How to read a formula
H20
This is a subscript. It tells us how many atoms of that element exist in one unit of that compound.
Hydrogen is made of 2 H atoms and 1 O atom.
No subscript is used when only one atom of an element is present.

16. Let’s try it…
Using your white board tell how many atoms there are in each element.
Sulfuric Acid H2SO4
2 Hydrogen
1 Sulfur
4 Oxygen
Hydrogen Peroxide H2O2
2 Oxygen

17. And some more formulas…
Carbon Dioxide CO2
1 Carbon
2 Oxygen
Carbon Monoxide CO
1 Oxygen
Calcium Carbonate (Found in shells, eggshells, antacid) CaCO3
1 Calcium
3 Oxygen

18. Compound Review
 A pure compound has the same elements and the same amount of elements all of the time
Elements are chemically combined
Compound properties are different from the properties of the elements
They cannot be separated physically
Physical properties such as boiling point or melting point of pure substances are do not change

19. Mixtures
A mixture is a combination of two or more substances where there is no chemical combination or reaction.

20. A mixture is a combination of two or more substances where there is no chemical combination or reaction.

21. Mixtures combine physically in no specific proportions. They just mix.

22. Solids, liquids and gases can be combined to create a mixture.

23. Mixture Types
MIXTURES MAY BE HOMOGENEOUS OR HETEROGENEOUS

24. Homogeneous Mixtures Homogeneous Mixtures:
The prefix: "homo"- indicates the same
Have the same uniform appearance and composition throughout

25. Solutions
SOLUTIONS
are homogeneous mixtures

26. What is a solution? A solution is a mixture of two or more substances.
At least two substances must be mixed in order to have a solution

27. A solution has two parts
The substance in the smallest amount and the one that DISSOLVES is called the SOLUTE
The substance in the larger amount is called the SOLVENT - it does the dissolving
IN most common instances water is the solvent
                        

28. Examples of solutions
Salt water
Clean Air
Vinegar

29. Heterogeneous Mixtures:
The prefix: "hetero"- indicates difference
A heterogeneous mixture consists of visibly different substances or phases
Two or more parts can be seen

30. Examples:
Pizza
Sandwich
Chex Mix

31. Suspensions A SUSPENSION is a heterogeneous mixture of large particles
These particles are visible and will settle out on standing
Examples of suspensions are: fine sand or silt in water or Italian salad dressing

32. Compounds vs Mixtures Mixtures Compounds Not chemically combined
Combine chemically forming molecules
Can combine in any proportion
Combine in set proportions
Separated chemically
Separated physically

33. Comparing Elements, Compounds & Mixtures
What are they made up of?
Can they be broken down? If yes, how?
Do they keep or lose their original properties?
Draw what the particles look like.

34. Identify the following with as many terms as apply
Table salt
Salad
Mayonnaise
Italian dressing
Pepsi
Oxygen
Hydrogen
Water
Mixture
Element
Compound
Suspension
Colloid
Solution
Homogeneous
Heterogeneous