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SWBAT Categorize electrons by energy levels, sublevels, and orbitals using the atomic model
SWBAT create Bohr models and atomic diagrams using knowledge of electron energy levels

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Lecture and guided notes (15 min)
White board practice (15 min)
Bohr Model poster (20 min)
Practice questions (15 min)
Exam Alignment Guides (10 min)

What is the difference between the models in group a and group b
Group A Group B

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Niels Bohr : (1913) proposed that an electron is found only in specific circular paths, or orbits , around the nucleus
Each electron has a fixed energy level
Energy level

1.
Draw a small circle below the text that will represent the nucleus of the atom
Carbon
Atomic # = 6
Mass # = 12
Atomic mass = 12.011 amu
C 6p +
6n 0
In the circle write: the elemental symbol the number of
Protons and
Neutrons

2.
Draw a larger circle around the nucleus circle to represent the first energy level for electrons
Carbon is in Period two and therefore needs two energy levels
Carbon
Atomic # = 6
Mass # = 12
Atomic mass = 12.011 amu
C 6p +
6n 0
Add more circles outside to include all of the energy levels you need for the atom.
This is the same as the period row

3.
Add electrons, as small dots, to each energy level as allowed until you have the proper number of electrons .
The number of electrons should be equal to the number of protons or atomic number
Carbon
Atomic # = 6
Mass # = 12
Atomic mass = 12.011 amu
C 6p +
6n 0
Energy
Level
# of e -
1
2
3
4
2
8
18
32

You now have a complete Bohr Diagram
Carbon
Atomic # = 6
Mass # = 12
Atomic mass = 12.011 amu
C 6p +
6n 0

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Draw the Bohr model for sodium (Na)
◦ How many protons and neutrons does sodium have?
◦ How many electrons does sodium have?
◦ How many energy levels does sodium have
(hint: what row is it in?)

Richard Feynman

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Electrons move around the nucleus at certain energy levels complicated.
, but it’s a little more
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Within these levels, we have energy sublevels an electron is
, which are orbitals regions likely to be found .
, or where
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For example, you are an 11 th grader (your energy level), but you are likely to be found in Chemistry, Algebra II, and Spanish III
(your regions, your orbitals).

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Atomic orbital : describes the electron’s probable location
Principal quantum numbers : indicate the relative sizes and energy of atomic orbitals, there are 4 of these numbers
◦ ex: principal energy level, n
Energy sublevels : describes the shape of the orbital, can be s, p, d or f

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When it’s spinning fast, we can’t see the blades but we know they’re likely to be in a certain area.
That’s what the orbital tells us about the electron!

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Each orbital corresponds to a different shape s orbitals
◦ spheres
2 electrons
 p orbitals
◦ dumbbell-shaped
6 electrons

 d orbitals
◦ like balloons tied together or balloons with a hula hoop
10 electrons
 f orbitals
◦ like balloons with cupcake wrappers or bracelets?
14 electrons

Principal Energy Number of
Level Sublevels
Type of Sublevel n = 1 n = 2 n = 3 n = 4
1
2
3
4
1s (1 orbital)
2s (1 orbital), 2p (3 orbitals)
3s (1 orbital), 3p (3 orbitals),
3d (5 orbitals)
4s (1 orbital), 4p (3 orbitals),
4d (5 orbitals), 4f (7orbitals)
Maximum number of electrons
2
8
18
32

1.
2.
3.
4.
What is the energy level for carbon?
What sublevels are contained in the carbon atom?
What orbitals are related to each of these sublevels?
How many electrons are in each orbital and sublevel?

Principal
Energy
Level
Sublevels Corresponding number of orbitals
Number of electrons n = 1 1s 1 orbital 2 n = 2 ______
2p
1 orbital
______________
______
2

Principal
Energy
Level
Sublevels Corresponding number of orbitals
Number of electrons n = 1 1s 1 orbital 2 n = 2 2s
2p
1 orbital
3 orbitals
2
2

1.
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3.
4.
What is the principal energy number?
How many sublevels does P have?
How many orbitals does P have?
How many protons, neutrons and electrons does P have?

1.
2.
3.
4.
What is the principal energy number?
How many sublevels does Cr have?
How many orbitals does Cr have?
How many protons, neutrons and electrons does Cr have?

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2.
3.
4.
What is the principal energy number?
How many sublevels does Br have?
How many orbitals does Br have?
How many protons, neutrons and electrons does Br have?

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Kayla claims that the n=2 energy level has 4 electrons because it has 4 orbitals. Is she correct? Why or why not?

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Troy claims that the principal energy level always equals the number orbitals at that level, and so energy level n=3 has 3 orbitals. Is Troy correct?
Why or why not?

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Pick a paper with an element on it.
Make a drawing of the Bohr model for that element
Answer the questions (from the small question sheet) on the back of your model

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Complete the following practice problems p.132 #7 p. 152 #32, 33, 34, 37, 38

1.
2.
Draw the orbitals for n = 1,2 and
3 and write how many electrons can be in that energy level
Draw the Bohr model for oxygen, sodium and silicon