Catalyst
Nothing in the world is worth having or
worth doing unless it means effort, pain,
and difficulty…I have never in my life
envied a human being who led an easy
life.
-Theodore Roosevelt
Average % Correct for a 3
on the AP Chem Exam
Average % Correct for a 4
on the AP Chem Exam
Average % Correct for a 5
on the AP Chem Exam
Ask Yourself…
Unit 1 Test
Thoughts on Exam 1
• Naming Compounds – Homework for the weekend
• Calculator training after school today. You all need to
attend…way too many calculator errors were seen
• Saturday school in the near future! OPTIONAL but we all
need it
• Don’t know the answer? Try to get something on the paper!
• Units? Units? Where for ought thou units?
• Homework…NOT OPTIONAL
• Change in homework policy
64.90
64.70
64.59
Total Score (%)
64.50
64.30
64.10
64.04
63.90
63.70
63.50
Period 5
Period 2
40.0
35.0
30.0
25.0
Period 5
Perod 2
20.0
15.0
10.0
5.0
0.0
A
B
C
NP
Today’s Learning Targets
Analyze the Data
Ionic Bonding
Ionic Bond Formation
Coulomb’s Law
q1q2
F= 2
d
Lattice Energies
Covalent Bonding
Lewis Structures
Exceptions to the Octet Rule
Class Example
Table Talk
• It’s 10 years in the future and you are teaching your
own AP Chemistry course (since we all know that is
what you all want to do after college)
• You give a quiz on Lewis Structures. Correct this
struggling student’s paper and provide comments
Formal Charges
• Many compounds have more than 1 possible Lewis
structure.
• Formal charges tells us the “right” Lewis structure.
• Formal Charge – The charge an element would
have if all electrons were shared equally.
• The “best” structure has:
1. Atoms that have formal charges closest to 0
2. Highest negative charge on the most
electronegative atom
Calculating Formal Charges
• To calculate formal charge:
-
-
# Valence e - (# of Bonds + # Unshared e )=Formal Charge
Class Example
Table Talk
Class Example
Table Talk
White Board Practice
• Answer the following questions on your white board
• Don’t put up the boards until I tell you too!
Question 1
• Label the formal charges on the molecule below
Question 2
• Label the formal charges on the compound below
Question 3
• Label the formal charges on the compound below
Question 4
• Draw the Bohr structure for BI3
Question 5
• Draw the Bohr structure for SI5
Question 6
• Draw the Lewis structure for XeF6
Closing Time
• Naming Practice
• Test Error Analysis Worksheet
• Post – Lab Questions for Lab 3 due Tuesday. NO
LONGER A LAB REPORT! Your Welcome 