Chemical Bonding and Chemical Interactions

1. Physical Science
Date: July 19, 2014
Objective: I can predict the oxidation
number and number of valence electrons
for an element as well as draw Lewis dot
diagrams.
To Do:
• Complete Catalyst (5 minutes)
• Have binder ready & periodic table out

2. Catalyst: Review
Subatom
ic
Particle
Charge Location Size
prot
on
electro
n
neutro
n
positiv
e
negativ
e
neutral
Inside
nucleus
Inside
nucleus
outside
nucleus
1 amu
1 amu
1/200
0
amu

3. Catalyst: Review
② Compare a period to a group on the
periodic table.
• A period is a row on the periodic table
• There are 7 periods
• A group is a vertical column
• There are 8 representative groups
• Both contain elements and provide
useful information about atoms

4. Catalyst: Review
Perio
ds
Group
s

5. Catalyst: Review
③ What can the period or row tell you
when drawing Bohr models?
• A period or row tells you how many
rings or shells to draw on a Bohr
model.

6. Catalyst: Review
④ Sodium
④ Carbon
Remember:
• 1st ring: 2 e-
• 2nd ring: 8 e-
• 3rd ring: 18
e-

7. Today’s Objective
Objective: I can predict the oxidation
number and number of valence electrons
for an element as well as draw Lewis dot
diagrams.

8. Vocabulary
Valence electron: An electron on
the outermost energy level in an
atom 1 valence
e-
4 valence
e-

9. Valence electrons
• Atoms in the same family have the
same # of valence electrons
• Elements in the same family have
similar properties

10. Valence electrons
1
2 3 4 5 6 7
8Label your periodic tables as
shown here:

11. popcorn
• We will play popcorn around the
classroom
• We will ask questions about valence
electrons
• For example, “How many valence
electrons does Nitrogen have?”
• If you answer correctly, you may choose
the next student to ask a question to

12. Vocabulary
• Oxidation Number: Refers to the
number of electrons lost or gained
during chemical bonding
• When metals and nonmetals form
compounds, they lose or gain valence
electrons

13. Vocabulary
• Ionic Bond: A bond between a metal
and a nonmetal
• Ion: An atom with a positive or negative
charge

14. Ions
• An ion is an atom that has a positive
or negative electric charge
• Represented by the plus or minus sign
Na+
• Plus sign tells
me that this
sodium atom
gave an electron
away

15. Oxidation #
+1
+2 +3 +-4 -3 -2-1
0Label your periodic tables as
shown here:

16. Oxidation #
• Metals have a positive charge because
they lose electrons
• Nonmetals have a negative charge
because they gain electrons

17. Lewis dot diagrams
• Bohr diagrams help us see electron
configurations for atoms
• Bohr diagrams help us understand
reactivity
• Lewis dot diagrams
show valence
electrons only

18. 1. Write the chemical symbol
2. Find the # of valence electrons (group #)
3. Draw the valence electrons (cross method)
Drawing Electron dot diagrams
Valence electrons = 7
Cl

19. Examples:

20. Practice
• Using your dry erase board, draw dot
diagrams for the element I call out
• When I say to, hold up your dry erase
board
• Work independently

21. Activity
• Complete the Mix & Match Activity with
your table partner
• When finished, raise your hand and I will
check your work
• You have 25 minutes to complete
correctly
• Pick-up the Periodic Table Challenge
when finished

22. Exit ticket
• Complete the Exit Ticket
• You may use your periodic table
• Keep eyes on your own paper
• 10 minutes