1. After today, you will be able to…
Explain how ionic and covalent bonding occurs
Write dot diagrams for elements in the s and p blocks
Determine the number of valence electrons in a particular atom

3. Unit: Chemical Bonding
Day 1 - Notes
Unit: Chemical Bonding
The Basics of Chemical Bonding

4. Two types of bonding:
Ionic Bonding: Involves a transfer of electrons. One element loses electrons and the other gains electrons.
Covalent Bonding: Involves a sharing of electrons. Atoms will share in order to reach a stable electron configuration.

5. The Octet Rule
Atoms will gain or lose enough electrons to make them isoelectronic with a noble gas. -Except for H and He, there will be 8 electrons in their valence shell

6. Electron Dot Structures
A way to show the number of valence electrons in an atom
Valence electrons must be labeled like this: X 5 2 3 1 6 8 4 7

7. The number of valence electrons can be determined by the group the elements are in – s and p blocks only!
Group # 1 2 13 14 15 16 17 18
Valence E-
E- Dot Strux 1 2 3 4 5 6 7 8

8. Valence electrons determine chemical reactivity – elements in the same group behave the same!1 2 13 14 15 16 17 18
Electron activity
Charge
Group #
Lose/ Gain 4
Lose 1
Lose 2
Lose 3
Gain 3
Gain 2
Gain 1 
+/- 4
Gain 1 X +1 +2 +3 -3 -2 -1 

9. Introduction to Ionic Bonding
An ionic bond forms from the attraction between + and – ions.
An ionic compound is made up of crystals
A crystal consists of a 3D, repeating pattern of alternating + and – ions
Formula unit: the lowest whole number ratio of ions
Ionic compounds have high melting points
Conduct electricity when melted or dissolved
Example: NaCl

10. After today, you will be able to…
Write formulas for ionic compounds
Explain what an empirical formula is
List and explain the properties of ionic bonds
Show bonding in ionic compounds using electron dot diagrams

11. Unit: Chemical Bonding
Day 2 - Notes
Unit: Chemical Bonding
Properties and Bonding of Ionic Compounds

12. Properties of Ionic Compounds…
Ionic bonds are very strong
Are solids at room temperature
Have high melting and boiling points
Made of a metal and a nonmetal
Does not conduct electricity in solid state, but does in the liquid and aqueous states
Aqueous: dissolved in water

13. Examples: The formation of ionic compounds
Use electron dot structures to predict the compound that would form between Sodium and Fluorine:
To write the formula write the metal first, then the nonmetal… F Na
NaF

14. Examples: The formation of ionic compounds
Use electron dot structures to predict the compound that would form between Magnesium and Chlorine: Cl Mg
MgCl2 Cl

15. Examples: The formation of ionic compounds
Use electron dot structures to predict the compound that would form between Aluminum and Sulfur: Al S Al S
Al2S3 S

16. Empirical Formulas
The chemical formula for an ionic compound is arranged in the smallest whole-number ratio is known as an empirical formula.
Example: Mg3N2 vs. Mg6N4

17. After today, you will be able to…
Write structural formulas and dot formulas for covalently bonded molecules
Identify shared and unshared electrons
Explain the difference between single, double, and triple bonds - and write them using structural formulas/dot formulas

18. Unit: Chemical Bonding
Day 3 - Notes
Unit: Chemical Bonding
Covalent Bonding Basics

19. Covalent Bonding A sharing of electrons.
A single covalent bond is made up of two electrons
One electron is donated to the bond from each atom
Covalent bonding occurs between nonmetals only
Atoms that are covalently bonded are called molecules or molecular compounds.

20. Properties of Molecular Compounds
Covalent bonds are much weaker than ionic bonds
Much lower melting and boiling points
Is a solid, liquid, or gas at room temperature
Non-conductors in any state

21. Properties of Molecular Compounds
The chemical formula for a covalently bonded group of atoms is called a molecular formula.
Indicates the exact makeup of one molecule.
Example: C6H12O6

22. 1 4 5 6 7 1 4 3 2 1 1 4 3 2 1 H Group 14 Group 15 Group 16 Group 17
# of valence electrons
# of electrons short
# of bonds made 1 4 5 6 7 1 4 3 2 1 1 4 3 2 1

23. Example: Write the dot and structural formula for: H2
Rough Copy (Work):
Dot Formula:
Lewis Structural Formula: H H
Single bond: A shared pair of two electrons.

24. Example: Write the dot and structural formula for: O2
Rough Copy (Work):
Dot Formula:
Lewis Structural Formula: O O
Unshared pair of electrons
Double bond: Two shared pairs of four electrons.

25. Example: Write the dot and structural formula for: N2
Rough Copy (Work):
Dot Formula:
Lewis Structural Formula: N N
Triple bond: Three shared pairs of six electrons.

26. Example: Write the dot and structural formula for: H2O
Rough Copy (Work):
Helpful tip: Put the atom in the middle that wants to make the most bonds! H
Dot Formula:
Lewis Structural Formula: O H O H

27. Example: Write the dot and structural formula for: ONF
Rough Copy (Work):
Dot Formula:
Lewis Structural Formula: O N F O N F