1. Compounds & Molecules
Compounds - made of 2 or more elements
and are chemically combined
Chemical bond - force that holds atoms
together
Formulas - represent compounds, made up
of subscripts and symbols

2. Compounds and Mixtures Differ
Mixtures are made of different substances
that are physically placed together.
Compounds are made of different atoms
that are chemically bonded together.
The substances in mixtures may exist in
any amount.
The atoms in compounds are in definite
proportions.

3. Mixtures do not have a chemical formula.
Compounds do have a chemical formula.
The substances in mixtures keep their
individual properties.
The atoms in compounds lose their

4. Examples of compounds
Water H2O
Salt (sodium chloride) NaCl
Table sugar C12H22O11

5. Compounds are always made of the same elements in the same proportions
H2O is water (2H:1O)
H2O2 is hydrogen peroxide (1H:1O)

6. 2 Types of Formulas
Molecular - H2O gives the number
and kinds of atoms
Structural - shows how the atoms are
bonded

7. Chemical structure affects the properties
Quartz (found in rocks) and Table salt
- exist as a large network of
bonded atoms
Sugar and water
- made of many separate
molecules

8. Quartz - forms crystals
- bond is very strong
- hard and inflexible solid
- high melting and boiling pt.
Sugar - forms molecules
- weaker bonds
- low melting and boiling pt.

9. Review Questions:
What does a formula represent?
What two things is a formula made of?
What are chemical bonds?
In this formula: C8H16O8, what is
the ratio of Carbon to Hydrogen?
4. In the above formula, how many total
atoms are there?
5. Name the two types of formulas.
Which type shows how the atoms bond?

10. Is the formula for water always H2O?
Are the atoms in a compound always
in the same proportion?
7. Make a T-chart to show 3 differences
between quartz and table sugar.
8. Define compound.
9. Make a T-chart to show 4 differences
between mixtures and compounds.

11. TYPES OF BONDING
Ionic - formed between oppositely
charged ions
- involves a transfer of electrons
- formed between a metal and
a nonmetal
- Na+ Cl NaCl
- form crystals

12. Covalent - sharing of electrons
- occurs between 2 nonmetals
- C + O > CO
(carbon monoxide)
- form molecules

13. Polyatomic ions - group of atoms that act as a single unit Examples:
Phosphate PO43-
Carbonate CO32-

14. Review Questions:
For Questions write Ionic or
covalent, depending on which is being described.
Involves a sharing of electrons
Involves a transfer of electrons
Forms molecules
Forms crystals
Formed between a (+) and a (-)ion
Between 2 nonmetals
Between a metal and a nonmetal

15. For questions 8 - 10, tell if the following
compounds have been formed by ionic
or covalent bonds.
MgCl2
9.CO
10.ZnF2

16. NAMING COMPOUNDS
Ionic compounds
metal listed first, nonmetal second
NaCl sodium chloride
(change second element letters
to “ide”)
Name these: NaF, CaCl2, HI

17. Writing Ionic Formulas
Give the formula for aluminum fluoride
Al charge is 3+
F charge is 1-
Have to balance to zero
Al is 3+ so need to make F 3-
F is 1- x 3 = 3 F’s AlF3

18. Give the formula for calcium chloride Ca charge is 2+
Cl charge is 1- (take times 2)
CaCl2
Give the formula for sodium oxide
_____?
Sodium Oxide: Na2O

19. Write formulas for ionic compounds made
between these atoms:
Li and O Be and Cl
Ca and O Mg and S
Al and O Na and S
Mg and Br Al and N

20. Naming Covalent Compounds
-prefixes are used to name compounds with 2 elements
CO2 carbon dioxide
N2O4 dinitrogen tetraoxide
Before showing water as dihydrogen monoxide do the activity handout about water as an article review opinion.

21. Try these
BI3
NaN3
SiO2
Boron Triiodide; Sodium trinitride; Silicon dioxide; Dihydrogen monoxide (water)- removed so can do the article review

22. -compounds that contain carbon Examples of carbon compounds
Organic Compounds
-compounds that contain carbon
Examples of carbon compounds
hydrocarbons- contain only C and H
methane CH4, butane C4H10
alcohols - C, H, and O
isopropyl alcohol C3H8O
This is for introduction, we will look at reactions and polymers later (in Q3 beginning) and in the lab.

23. Many organic compounds are
POLYMERS
Large molecules made of a repeating unit
Natural polymers - rubber, wood, cotton,
wool, protein, DNA
Man-made polymers - plastics, fibers like
rayon, nylon

24. Biochemical compounds are
organic
Examples:
Carbohydrates - sugars
Proteins - made of amino acids
Lipids - fats and oils
DNA - genetic material