1. CHEMICAL BONDING Lewis Dot Structures Ionic an Covalent Bonding
Formula Writing
Naming Compounds
Molecular Models
CHEMICAL BONDING
To play the movies and simulations included, view the presentation in Slide Show Mode.

2. Two types of chemical bonds
Bond Comparison
Ionic Bonds
Covalent bonds

3. Covalent Bonds vs. ionic Bonds
Atoms share electrons
Bonds between nonmetals and non metals
They are in MOLECULES
Ionic Bonds
Atoms transfer electrons
Bonds between metals and nonmetals
They are in IONIC COMPOUNDS
Lewis dot Structures have which type of Bond?

4. The type of bond can usually be calculated by finding the difference in electronegativity of the two atoms that are going together.

5. Electronegativity Difference
If the difference in electronegativities is between:
Ionic Bond: > 2.0
Polar Covalent: 0.4 – 2.0
Non-Polar Covalent: < 0.4 _
Example: NaCl
Na = 0.8, Cl = 3.0
Difference is 2.2, so
this is an ionic bond!
Look at the first slide to see which molecules may be polar

6. Ionic bonds and ionic compounds
How they combine –
Ionic compounds–
Ions –
Writing ionic formulas –

7. Let’s look at Ionic bonds
Ionic bonding is the attraction between positive and negative ions.
Two kinds of ions
Cations - + ions.
Anions - neg ions.
Electrons are transferred from one atom to another.
Draw dot structures for magnesium and oxygen

8. Ionic compounds have ionic bonds and…
Electrically neutral. MgCl2
High melting points (very strong bonds!)
Brittle.
Dissolve in water and then conduct electricity.
Molton ionic compounds are excellent conductors.
Cl Mg Cl

9. Write out these ions-- Chloride Magnesium ion Fluoride Aluminium ion
Positive ions state the name then “ion”
Negative ions end in “–ide”.
Chloride
Magnesium ion
Fluoride
Aluminium ion
Ions that are in the transition metals:
Look for the little number above the
symbol… that is the oxidation state.
Zinc ion
Silver ion
Iron III ion
Iron VI ion

10. Review how to write ionic formulas
Magnesium phosphide
Lithium bromide
Aluminium oxide
Iron II oxide
Ionic Formulas:
Write out ions and switcheroo away!

11. Match making Exercise!
Circle Round Exercise

12. Ionic compounds with polyatomic ions (gold sheets)
What are the charges of these ions? Write them out…
Phosphate
Sulfate
Hydroxide
Practice:
Sodium phosphate
Calcium oxalate
Silicon chromate
Zinc hydroxide
Ionic compounds with polyatomic ions (gold sheets)

13. Covalent bonds and molecules
Two ways to write molecular formulas –
Three types of covalent bonds –
Covalent prefixes –
Writing covalent formulas –

14. Molecules are shown two ways
Can be a combination of 2 or a million elements.
Molecular Formula
C6H12O6
not CH2O
(empirical formula)
Structural Formula H N H H

15. Three types of covalent bonds

16. Covalent prefixes to determine molecularformula
Name these molecules: CO
CO2
H2O
CF4
SI2
N3O
Number of Atoms
Prefix 1
mono - 2
di - 3
tri – 4
tetra – 5
penta – 6
hexa – 7
hept– 8
oct– 9
non – 10
dec –

17. Double and even triple bonds are commonly observed for C, N, P, O, and S
H2CO
SO3
C2F4

18. Now You Try One! Draw Sulfur Dioxide, SO2
Use the force… (or bonds) to hold atoms together