1. Non-Metals Metalloids Metals Periods Families(Groups)
--same # valence electrons
Non-Metals
Metals
Metalloids
As a general rule, metals don’t like to form bonds(compounds) with other metals(They will with themselves). Metals(+ ions) would rather form bonds with nonmetals(- ions)!!

3. Covalent Bonding Involves the sharing of electrons.
Covalent bonds form between nonmetals and nonmetals.

4. Lewis Dot Structures (aka Electron Dot Diagrams)
Lewis dot structures are a shorthand to represent the valence electrons of an atom.
The structures are written as the element symbol surrounded by dots that represent the valence electrons.

5. Lewis Dot Structures(cont.)
Lewis structures can also be used to show covalent bonding between atoms.
The bonding electrons are placed between the atoms and can be represented by a pair of dots or a dash (each dash represents one pair of electrons, or one bond).

6. Show the Lewis Dot Structures for the following compounds:
O2 F2 H2O

7. Covalent Bonds(cont.)
Sometimes electrons are shared equally among nonmetals in a covalent bond. Sometimes they are not.
It’s as if one element is pulling on the electrons just a little bit harder than the other.

8. Covalent Bonds(cont.) Polar Covalent Bonds Non-Polar Covalent Bonds
One element is pulling harder on the electrons than the other(s).
Unequal sharing of electrons.
This cause them to set up “poles”.
One element will become slightly positive and the other slightly negative.
Both elements are pulling just as hard on the electrons.
Equal sharing of electrons.

9. Solutions with Polar and Non-Polar Compounds:
As a general rule, “Likes dissolve Likes”
Polar substances dissolve polar substances!
Ex. H2O dissolves NaCl(all ionic compounds are polar)
Non-Polar substances dissolve Non-polar substances.
CO2 will dissolve in ethanol(CH3CH2OH) because both are non-polar.
Polar substances will not dissolve in Non-Polar substances!!!
Water and Oil do not mix!!!

10. Which compound is least affected by temperature?
Which compound’s solubility decreases as temperature increases?

11. How many grams of KNO3 will dissolve in 100 g of water at 60o C?

12. At what temperature will approximately 95 g of NaNO3 dissolve in 100 g of water?
30 oC

13. At what temperature will the same amount of KNO3 and NaNO3 dissolve in 100 g of water?
~ 68 oC

14. Name the following compounds:
Sodium Chloride
NaCl
CaO KF
Na2CrO4
Ca(ClO3)2
Al2(CO3)3
Calcium Oxide
Potassium Fluoride
Sodium Chromate
Calcium Chlorate
Aluminum Carbonate

15. Writing Chemical Formulas:
Lithium and Selenium Li+1Se-2 Li2Se Calcium and Chlorate Ca+2ClO3-1 Ca(ClO3)2 Beryllium and Phosphorus Be+2P-3 Be3P2 Gallium and Carbonate Ga+3CO3-2 Ga2(CO3)3

16. Write the formulas for the following compounds:
Calcium Phosphate
Ca+2PO4-3
Ca3(PO4)2
Aluminum Acetate
Al+3C2H3O2-1
Al(C2H3O2) 3
Francium Phosphide
Fr+1P-3
Fr3P

17. Cu+2F-1 Co2S3 Co+3S-2 Fe2O3 Fe+3O-2
Determine the oxidation state of both elements in the following examples:
CuF2
Cu+2F-1
Co2S3
Co+3S-2
Fe2O3
Fe+3O-2

18. Chemical Equations: Reactants “yield” Products Reactants Products
Must know the 4 types of chemical reactions:
Decomposition AB A + B
Synthesis A + B AB
Single Replacement AB + C AC + B
Double Replacement AB + CD  AD + CB