1. Today:
Please put your phones in the basket and sit in your assigned seat. You must sit quietly and respectfully. Once you’re seated, get started on your quiz.

2. New Policy:
Due to the lack of respect for myself and this class, we are adopting a new policy in all of my classroom that is as follows: 1) Talking during a lesson – 3 strikes and then a detention. 2) Arguing with the teacher – automatic detention. 3) Continue to argue – 2 days of detention. 4) Continue to argue – 3 days of detention. 5) If you continue – sent to office immediately. Your parents will be informed in all cases.

3. Violating the #1 class rule includes:
1) Not in your seat ready to learn when the bell rings – will receive a tardy. 2) Talking back to the teacher. 3) Arguing with me at all. 4) Disrupting class or talking during the lesson. 5) Not doing your work and distracting other students. 6) Getting up from your seat without asking during a lesson. 7) Not putting your phone in the basket. 8) Talking during a lesson without raising your hand. Each of these violations will result in one or more detentions

4. Informing your parents:
Since we have parent-teacher conferences tomorrow, I will be sending a letter home with each parent that I talk to and informing them of my new policy. For those parents who do not come, I will be ing and contacting personally. This new method is designed to create an environment in the classroom that allows every student an equal opportunity to learn.

5. Next:
We are going to take some notes. You will be on a 3 strikes and you’re out basis from now on. The third warning, will get you sent straight to the office.

6. The Nature of Covalent Bonding
8.2
The colors in this map indicate the concentrations of ozone in various parts of Earth’s atmosphere. Oxygen atoms can join in pairs to form the oxygen you breathe and can also join in groups of three oxygen atoms to form ozone.

7. The Octet Rule in Covalent Bonding
8.2
The Octet Rule in Covalent Bonding
The Octet Rule in Covalent Bonding
What is the result of electron sharing in covalent bonds?

8. The Octet Rule in Covalent Bonding
8.2
The Octet Rule in Covalent Bonding
In covalent bonds, valence electrons are shared between two atoms so that atoms attain the electron configurations of noble gases.

9. 8.2
Single Covalent Bonds
Single Covalent Bonds
How are shared electrons represented by electron dot structures?

10. 8.2
Single Covalent Bonds
Two atoms held together by sharing a pair of electrons are joined by a single covalent bond.

11. 8.2
Single Covalent Bonds
An electron dot structure such as H:H represents the shared pair of electrons of the covalent bond by two dots.

12. Structural Formulas
Structural Formulas:
A structural formula represents the covalent bonds by dashes and shows the arrangement of covalently bonded atoms.
A single covalent bond occurs when two atoms share ONE PAIR of electrons, and is represented by one line between two atoms.
Example: H ̶ H

13. 8.2
Single Covalent Bonds
The halogens form single covalent bonds in their diatomic molecules. Example: fluorine molecule

14. 8.2
Single Covalent Bonds
A pair of valence electrons that is not shared between atoms is called an unshared pair, also known as a lone pair or a nonbonding pair.

15. 8.2
Single Covalent Bonds
Hydrogen and oxygen atoms attain noble-gas configurations by sharing electrons.

16. The ammonia molecule has one unshared pair of electrons.
8.2
Single Covalent Bonds
The ammonia molecule has one unshared pair of electrons.

17. Methane has no unshared pairs of electrons.
8.2
Single Covalent Bonds
Methane has no unshared pairs of electrons.

18. 8.1
Section Assessment

19. Section Assessment

20. 8.1
Section Assessment

21. for Conceptual Problem 8.1
Section Assessment
Problem Solving 8.8 Solve Problem 8 with the help of an interactive guided tutorial.

22. Next:
You have a worksheet to work on and turn in before the end of class. You’re homework will be found online. (school website)

23. Double and Triple Covalent Bonds
8.2
Double and Triple Covalent Bonds
Double and Triple Covalent Bonds
How do atoms form double or triple covalent bonds?

24. Double and Triple Covalent Bonds
8.2
Double and Triple Covalent Bonds
Atoms form double or triple covalent bonds if they can attain a noble gas structure by sharing two pairs or three pairs of electrons.

25. Double and Triple Covalent Bonds
8.2
Double and Triple Covalent Bonds
A bond that involves two shared pairs of electrons is a double covalent bond.
A bond formed by sharing three pairs of electrons is a triple covalent bond.

26. Double and Triple Covalent Bonds
8.2
Double and Triple Covalent Bonds
Each oxygen atom needs two electrons to obey the octet rule, thus 2 oxygen atoms share two pairs of electrons.
Oxygen and nitrogen are the main components of Earth’s atmosphere. The oxygen molecule is an exception to the octet rule. It has two unpaired electrons. Three pairs of electrons are shared in a nitrogen molecule.

27. Double and Triple Covalent Bonds
8.2
Double and Triple Covalent Bonds

28. Double and Triple Covalent Bonds
8.2
Double and Triple Covalent Bonds
Carbon dioxide gas is soluble in water and is used to carbonate many beverages. A carbon dioxide molecule has two carbon-oxygen double bonds.
Carbon dioxide gas is soluble in water and is used to carbonate many beverages. A carbon dioxide molecule has two carbon–oxygen double bonds.

29. Double and Triple Covalent Bonds
8.2
Double and Triple Covalent Bonds
Carbon dioxide (CO2)
Oxygen and nitrogen are the main components of Earth’s atmosphere. The oxygen molecule is an exception to the octet rule. It has two unpaired electrons. Three pairs of electrons are shared in a nitrogen molecule.

30. Today:
Please put your phones in the basket and get out a piece of paper and something to write with. Please hang on to your homework assignments from yesterday so we can work on them today.

31. Bond Dissosociation energy:
The energy required to break the bond between two covalently bonded atoms is known as bond dissociation energy.
A large bond dissociation energy is needed for a strong covalent bond.

32. Exceptions to the octet rule:
The octet rule cannot be satisfied in molecules whose total number of valence electrons is an odd number. There are also molecules in which an atom has fewer, or more than a cmplete octet of valence electrons. Example: Nitrogen Dioxide (NO₂) molecule, has a total of seventeen valence electrons, an odd number, which leaves an unpaired electron.

33. Here are the rules for drawing Lewis Structures:
Next:
Here are the rules for drawing Lewis Structures:
First, find the number of valence electrons from the group number.
Then, set up the atoms, so that they can have bonds between them (1 bond = 2 valence electrons)
Then, add the remaining valence electrons around the atoms.
Each atom should have 8 valence electrons EXCEPT Hydrogen which is full with 2.
If there is not 8, you may need a double covalent bond = 4 valence electrons between atoms.

34. Please break up into groups of 3-4 and get out your homework assignments from yesterday. If you have already finished, please help students who do not understand. I will come around to each groups and try and help you individually. You may use the white board if you would like. Take about 20 minutes on this.

35. Practice drawing the following Lewis Structures: H₂S PH₃ CIF SBr₂ C₃H₈
Next:
Practice drawing the following Lewis Structures: H₂S PH₃ CIF SBr₂ C₃H₈

36. 8.2 Section Quiz.
8.2.

37. 8.2 Section Quiz.
1. In covalent bonding, atoms attain the configuration of noble gases by
losing electrons.
gaining electrons.
transferring electrons.
sharing electrons.

38. 8.2 Section Quiz
2. Electron dot diagrams are superior to molecular formulas in that they
show which electrons are shared.
indicate the number of each kind of atom in the molecule.
show the arrangement of atoms in the molecule.
are easier to write or draw.

39. 8.2 Section Quiz
3. Which of the following molecules would contain a bond formed when atoms share three pairs of electrons?
Se2
As2
Br2
Te2

40. END OF SHOW