This document summarizes a chemistry lesson on chemical bonds. Students are instructed to answer questions about why unstable isotopes decay and how nuclear reactions differ from chemical reactions. The lesson defines chemical bonds as holding atoms together to form compounds and molecules, involving only valence electrons. It explains that atoms form bonds to achieve stable electron configurations like noble gases, following the octet rule of having 8 valence electrons.

1. Launch: 10/22
 Grab your binder and immediately take a seat
 Answer the following two questions in complete
sentences:
1. Why do unstable isotopes go through radioactive
decay?
2. How are nuclear reactions different from chemical
reactions?

2. What is a chemical bond?
Mr. Heffner
10/22/09

3. What is a chemical bond?
 Chemical bonds…
 hold atoms together to make compounds and molecules.
Chemical Bond
O
H H

12. What is a chemical bond?
 Chemical bonds form during chemical reactions
 Only the valence (outer) electrons are involved in
bonding!

13. What is a chemical bond?
 Chemical bonds form during chemical reactions
 Bill Nye video
 List 4 chemical reactions from the video.
 What gas was responsible for making our Pop Rockets
pop?

14. Why do atoms form bonds?
 Atoms form bonds…
 to become more stable.
 The most stable atoms are the noble gases
 They have 8 valence electrons
 All other atoms want to be like the noble gases

15. Why do atoms form bonds?
 The octet rule is…
 oct- means 8
 Like octagon & octopus
 that all atoms want to have 8 valence electrons

16. Foldable
 Fold in half 3X, then fold in windows
 Key terms:
 Chemical bond
 Octet rule
 Valence electrons (include the trick)
 Quiz your partner (2 min)

17. Practice Questions
 Practice Questions Worksheet
 Answer in complete sentences!

18. Exit Slip
1. Chemical bonds
a. are always repulsive forces.
b. form between atoms to make compounds.
c. are not found in certain molecules like H2S.
d. take a large amount of energy to form.

19. Exit Slip
2. Which subatomic particles are responsible for
chemical bonding?
a. protons
b. electrons
c. valence electrons
d. neutrons

20. Exit Slip
3. Chemical bonds form because
a. isotopes need to go through nuclear reactions to
become more stable.
b. electrons on one atom attract electrons on another.
c. atoms want to have electron configurations like the
halogens.
d. atoms want to be stable and have a full valence ring.

21. Exit Slip
4. The octet rule states that
a. all atoms want to have 8 valence electrons.
b. all atoms want to have 18 valence electrons.
c. the noble gases are the least stable atoms.
d. all atoms want to have 8 protons, 8 neutrons, and 8
electrons.

22. Exit Slip
5. Which of the following atoms have a full octet?
a. oxygen (O)
b. iodine (I)
c. krypton (Kr)
d. calcium (Ca)

23. Homework
 Finish practice questions