1. Date: October 13, 2015
Aim #15: What role do electrons play in chemical bonding?
HW:
Worksheet- Counting Valence Electrons (back)
Quiz (Inorganic Chemistry)- Wednesday 10/21 & Thursday 10/22 (day of double period)
Do Now: Warm-Up Notebook
Date Title of Activity Page #
10/10 Chemistry Review 30

3. What determines an atom’s reactivity?
Electrons
2nd energy level
(8 electrons max)
1st energy level
(2 electrons max)
1st energy level
(2 electrons max)
Usually it is the electrons in the highest energy level
of an atom that determine how that atom reacts

4. Valence Electrons The number of electrons present in the highest
energy level.
How many valence electrons
does this atom have? 1
The valence electrons determine
the kinds and number of bonds
atoms can form.

5. C O Lewis Dot Structures
Dots are used to represent electrons in the outermost
shell (valence electrons). Dots are placed around the
symbol.
Let’s look at Carbon:
Let’s look at Oxygen: C O
Lewis Structures help us determine how many bonds
an atom can form.

6. Lewis Dot Structure Rules:
Determine the number of electrons in the outer
(valence shell).
2) Place a dot at the 12:00 position and continue
in a clockwise direction.
Do not form “electron pairs” until you have
completed a circuit.

7. What are chemical bonds?
Chemical bonds join atoms
together
Reactions between atoms result in filled outer energy
levels. This makes the atoms stable.

8. How many bonds can an atom form?4 2 1
Rule: Atoms can form bonds up to the number of
non-paired electrons in its valence energy level.

9. Lewis Dot Structures & Bonding

10. Aim #15: What role do electrons play in chemical bonding?
Date: October 14, 2015
Aim #15: What role do electrons play in chemical bonding?
HW:
Worksheet- How will they bond?
Textbook Guided Reading 2-2 due Thursday
Quiz (Inorganic Chemistry)- Wednesday 10/21 & Thursday 10/22 (day of double period)
Do Now: Warm-Up Notebook
Date Title of Activity Page #
10/

11. The metals are blue and nonmetals are yellow.

12. Types of Bonds: Covalent Bonds
Covalent Bond forms when two atoms share
electrons.
**Notice how the energy levels are no longer partially
filled.

13. Covalent Bonds: Sharing of electrons between two non-metals
In the diagram, two hydrogen atoms are bonded by a single covalent bond. The two atoms each share a pair of electrons.

14. Review: Number of Bonds an Atom Can Form
the number of bonds that an atom can form correlates to the number of electrons that is needed to have a full outer shell
H can form 1 covalent bond
O can form 2
N can form 3
C can form 4

15. Covalent Bonding
Sharing

16. Double or triple bonds:
Double Bond- atoms share two pairs of electrons between them
Triple Bond- atoms share three pairs of electrons between them

17. Short hand Method for Drawing Covalent Bonds
Straight lines can be used to represent a covalent bond between two atoms.
A single line is used to represent a single bond
Two lines are used to represent a double bond
Three lines represent a triple bond.
Some single, double, and triple bonds are shown below

18. Types of Bonds: Ionic Bonds
An ionic bond occurs when an atom transfers an
electron to another atom.
Na loses an electron and becomes a positive ion.
Cl gains an electron and becomes a negative ion.

19. Activity:
Diagram the electron shell configuration for Sodium and Chloride
What would have to happen for them to both have a full outer shell?
What Nobel Gas matches these configurations?

21. Ionic bonds: transfer of electrons between a metal and a non-metal
Example: Na+Cl-
Metals Lose (e-) and become positive ions (Cations)
Nonmetals gain (e-)and become negative ions (Anions)
The ions (atom with a charge) in a compound are attracted to each other due to opposite charges.

22. More Ionic Bonds * * * * * H F * * * * * Electron Is transferred
H becomes positive charged (H+)
F becomes negatively charged (F-)
**Notice how the energy levels are no longer partially
filled.

23. Oxidation & Reduction (REDOX)

25. Brain Pop- Chemical Bonds
stry/chemicalbonds/