Week 11 Chemistry
Isotopes, Electron Configuration
Warm Up: 4 Minutes
Stay in your own seat
Write the Learning
Target
You should be working SILENTLY
Calculate the smallest increment of energy that
is the quantum of energy, which an object can
absorb from a red light whose wavelength is 3.2
x 10-7 m.
Agenda

Warm Up: 8 minutes

Pre-Lab/Expectations: 7 minutes

Lab: A Penny for Your Isotopes: 25 minutes

Post Lab Discussion: 10 minutes

Closing: 3 minutes
Penny Lab
Take 62 seconds to read the
introduction paragraph.
Atomic mass vs. Mass Number

The Mass Number is the total number of Neutrons and
Protons

The Atomic Mass is an average of the different mass
numbers

It can be a decimal
Mass Number
13
𝐶
6
Atomic Mass
Problem
Is there a difference in the mass of pennies made
before 1982 versus pennies made after 1982?
Hypothesis
YOU HAVE 46 SECONDS WITH YOUR SHOULDER
PARTNER TO WRITE A TESTABLE HYPOTHESIS
BASED ON PRIOR KNOWLEDGE
Pre-Lab Questions
 What
is the difference between Atomic
Mass and Mass Number?
 What
is an isotope?
Lab Expectations

Work in assigned groups

Utilize proper safety practices

Raise your hand if you have a question
Do NOT Throw Pennies!
General information: How to do the lab
1.
Sort the pennies into two groups (pre-1982 and post-1982)
2.
Count number of pennies in each group
3.
Find mass of all pennies in each group TOGETHER
All pre-1982 together, All post-1982 together
4.
Find average mass of each group of pennies
𝑇𝑜𝑡𝑎𝑙 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑝𝑒𝑛𝑛𝑖𝑒𝑠 𝑖𝑛 𝑔𝑟𝑜𝑢𝑝
𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑝𝑒𝑛𝑛𝑖𝑒𝑠 𝑖𝑛 𝑔𝑟𝑜𝑢𝑝 =
𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑝𝑒𝑛𝑛𝑖𝑒𝑠 𝑖𝑛 𝑔𝑟𝑜𝑢𝑝
5.
Find average mass of all pennies
𝑇𝑜𝑡𝑎𝑙 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑝𝑒𝑛𝑛𝑖𝑒𝑠
𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑎𝑙𝑙 𝑝𝑒𝑛𝑖𝑒𝑠 =
𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑝𝑒𝑛𝑛𝑖𝑒𝑠 𝑖𝑛 𝑡𝑜𝑡𝑎𝑙
Penny Lab

You need a Bag of Pennies and your Brain

Good Luck!!!
What is the difference between these pennies?
Isotopes
 Atoms
of the same element that have
the same number of protons but
different numbers of neutrons
Examples:
13
6
C
12
6
C
Naming Isotopes

Put the mass number after the name of the
element

Example:
a. Carbon-12
b. Carbon- 14
Practice this idea…
By completing the
Isotope Penny Lab Extension Worksheet
Closing

Identify the two isotopes of a penny.

Define the term isotope.
Warm Up: 3 Minutes
Write the Learning
Target
Stay in your own seat
You should be working SILENTLY
What do these atoms have in common?
How are they different?
15
7
X
14
7
X
Agenda
 Warm
Up- 7 minutes
 Cornell
Style Notes/ Examples- 15 minutes
 Guided
Practice- 15 minutes
 Independent
 Closing-
Practice – 15 minutes
1 minute
Take out paper for notes
BLUE
RED
Atomic Mass

Weighted average mass of naturally
occurring isotopes of an element
** Each isotope has its own mass**
UNITS
FORMULA
AMU
Average Atomic Mass = (Percent in decimal x Mass) +
(Percent in decimal x Mass) +(Percent in decimal x Mass) +…
Relative Abundance
The percent occurrence (in decimal
form) of a specific isotope of an
element
Review: Converting percent to decimal
To convert a percent to decimal, divide it by 100
Examples:
72% = 0.72
24% = 0.24
8% = 0.08
Check Point
Convert 23.51% to a decimal
0.2351
What do you need to find Average
Atomic Mass?
1.Mass
of Individual Isotopes
2.Percent as a decimal
Check Point
What items are needed to calculate the atomic
mass of an element utilizing isotopes?
1.
Mass of individual isotopes
2.
Relative abundance (Percent in decimal)
I Do
There are 3 naturally occurring isotopes of the element Simonium.
The following is a list of these isotopes’ abundance in nature and
their rounded masses.
142.77 amu
32.0%
143.21 amu
6.4%
141.66 amu
61.6%
Calculate the average atomic mass of Simonium from these data.
We Do (CLASS)
Naturally occurring Chlorine (Cl) consists of two isotopes with a
mass of 35 and 37. Chlorine-35 has an abundance of 75.78%
and Chlorine-37 has an abundance of 24.22%. What is the
atomic mass of Chlorine?
We Do (Team)
Naturally occurring Carbon (C) consists of three naturally
occurring isotopes. Carbon-14 has an abundance of 23.10 %,
Carbon-12 has an abundance of 72.10 %, and Carbon-13 has
an abundance of 4.8%. What is the atomic mass of Carbon?
YOU DO
Naturally occurring Gallium (Ga) consists of two
naturally occurring isotopes. Gallium-69 has an
abundance of 60.11 % and Gallium-71 has an abundance
of 39.89 %. What is the atomic mass of Gallium?
Practice Makes Perfect…
85% MASTERY
Closing
What items do you need to find the
average atomic mass of an element?
Warm Up: 4 Minutes
Stay in your own seat
Write the Learning
Target
You should be working SILENTLY
Which of these examples of matter are
composed of more than one substance that
can physically be separated and have a
uniform composition?
a.
Copper, Cu
b.
Glucose, C6H12O6
c.
Double Cheese Burger
d.
Lemonade
Warm Up: 4 Minutes
Write the Learning
Target
Which of these examples of matter are
composed of more than one substance that
can physically be separated and have a
uniform composition?
a.
Copper, Cu
b.
Glucose, C6H12O6
c.
Double Cheese Burger
d.
Lemonade
Agenda

Warm Up- 6 Minutes

Discussion/ Cornell Style Notes- 15 Minutes

Guided Practice- 15 Minutes

Independent Practice- 15 Minutes

Closing- 2 Minutes
Goal for the Next Few Days
Construct Electron Configuration for
Elements
Aluminum
Take out paper for notes
BLUE
RED
Let’s Look at a Periodic Table…
1
1
IA
1
H
Periodic Table
2
IIA
13
IIIA
14
IVA
15
VA
16
VIA
17
VIIA
1.00797
2
3
Li
4
5
Be
B
6.939 9.0122
3
4
5
6
7
11
Na
12
Mg
22.9898 24.305
19
20
K
Ca
3
IIIB
21
Sc
4
IVB
22
Ti
5
VB
23
V
6
VIB
24
Cr
7
VIIB
25
Mn
Rb
Sr
Mo
Tc
85.47
55
87.62 88.905 91.22 92.906 95.94
56
57
72
73
74
[99]
75
Ba
7
N
8
O
9
F
He
4.0026
10
Ne
10.811 12.0112 14.0067 15.9994 18.9984 20.179
8
26
Fe
9
VIIIB
27
Co
10
11
IB
28
Ni
39.102 40.08 44.956 47.90 50.942 51.996 54.9380 55.847 58.9332 58.71
37
38
39
40
41
42
43
44
45
46
Cs
6
C
18
VIIIA
2
Y
La
Zr
Hf
Nb
Ta
W
Re
132.905 137.34 138.91 178.49 180.948 183.85 186.2
87
88
89
104
105
106
107
Fr
Ra
Ac
Ku
[223]
[226]
[227]
[260]
Ru
Rh
Pd
29
12
IIB
30
Cu
Zn
63.54
47
65.37
48
Ag
Cd
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
26.9815 28.086 30.9738 32.064 35.453 39.948
31
32
33
34
35
36
Ga
Ge
65.37
49
72.59 74.9216 78.96 79.909 83.80
50
51
52
53
54
In
Sn
As
Sb
Se
Te
Br
I
Kr
Xe
101.07 102.905 106.4 107.870 112.40 114.82 118.69 121.75 127.60 126.904 131.30
76
77
78
79
80
81
82
83
84
85
86
Os
190.2
108
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
192.2 195.09 196.967 200.59 204.37 207.19 208.980 [210]
109
At
Rn
[210]
[222]
Periods (or Energy Levels)
Where do Electrons Really Live?


Ok so, yes, Bohr was right. Electrons move around
the nucleus at certain energy levels, but it’s a little
more complicated.
Within these levels:
 Sublevels:
regions where an electron is likely to be
found.
 Orbitals: Part of a sublevel, more exact descriptions of
where an electron is found.
Location of the Electron
Energy Level
(n = 1, 2, 3…)
Sub-Levels
(s, p, d, and f)
Orbitals
Check Point
Celeste found that Helium had an
electron configuration of 1s2 , What
energy level would these electrons
be found on?
1st Energy Level
Warning!!! About to get all
Chemistry-language on you!
Sublevels

Each sublevel corresponds to a different shape

s sublevel
 spheres

p sublevel
 dumbbell-shaped
Sublevels

d sublevel
 like
balloons tied together or balloons
with a hula hoop

f sublevel
 like
balloons with cupcake wrappers
or bracelets
Check Point
What are the four types of sublevels?
S, P, D, F
More on Sublevels

Each sublevel has a different number of orbitals:
Sublevel
s
p
d
f
# of
orbitals
Copy This
Table
More on Sublevels

Each sublevel has a different number of orbitals:
Sublevel
s
p
d
f
# of
orbitals
1
More on Sublevels

Each sublevel has a different number of orbitals:
Sublevel
s
p
d
f
# of
orbitals
1
3
More on Sublevels

Each sublevel has a different number of orbitals:
Sublevel
s
p
d
f
# of
orbitals
1
3
5
More on Sublevels

Each sublevel has a different number of orbitals:
Sublevel
s
p
d
f
# of
orbitals
1
3
5
7
Pauli Exclusion Principle
 Each
atomic orbital may hold a maximum
number of TWO electrons, each with
opposite spin direction.
Check Point
 As
Raven composed the electron
configuration for Neon, she completely
filled the 2p sublevel. How many electrons
were in the p sublevel?
The Houses in the Neighborhood Must Be
Filled in Order!

The tree diagram shows us which sublevels are
filled with electrons first…follow the arrows!
Let’s Draw The Tree Diagram
Check Point
Which
orbital fills first, 3d or 4s ?
4s
Guided Practice
1.

Within each sublevel, there is a greater chance of
locating the electron, what is this area called?
How many electrons can be held in this portion of
the atom?
Within each sublevel, there is a greater chance of
finding the electron in an orbital. Orbitals can
hold two electrons each.
2.

Copper has a partially filled 3d sublevel. What is
the maximum number of electrons that can be
placed within the 3d sublevel? Why?
In the d sublevel of any energy level, 10 electrons
can be placed because all d sublevels have five
orbitals.
3.

Fluorine has an electron configuration of 1s22s22p5.
What number indicates the outermost energy level?
How many electrons are currently on the outermost
energy level?
The coefficient 2 indicates the outermost energy
level. Considering that s on the second energy level
has 2 electrons and p on the second energy level has
5 electrons, there are a total of seven electrons in
the outermost shell.
4.
How many f orbitals are in the third principal
energy level? Explain your answer.
According to the tree diagram, the third energy
level only has the s, p, and d sublevel (i.e.
orbitals). Therefore, there are ZERO f orbitals on
the third energy level.
Now You Practice!
Finished early? Start your homework:
 Construct the tree diagram 10 times to help with memorizing it.
Memorizing the tree diagram now will make your life SO
much easier in the future 
Closing
 Where
 How
do electrons live?
many live together?
Warm Up: 2 Minutes
Stay in your own seat
Write the Learning
Target
You should be working SILENTLY
Draw the tree diagram. Include all arrows.
POP QUIZ!
Put everything away except
for a pencil or pen
Backpacks, binders, and notes
on the floor
Draw the tree diagram. Include
all the arrows.
2. List the following sublevels in
order of increasing energy:
1.
3s, 2p, 4d, 5s, 4f, 1s
Agenda

Warm Up- 7 Minutes

Cornell Style Notes/ Examples- 15 minutes

Guided Practice- 15 minutes

Independent Practice – 13 minutes

Closing – 3 minutes
Take out paper for notes
BLUE
RED
Review of Yesterday
Energy Level (1, 2, 3)
Sublevel (s, p, d, f)
Neighborhood
Streets
Orbitals
Houses
Electrons
People
Key Points from Yesterday

Energy
Level
MAXIMUM of 2 electrons per orbital
Sublevel
s
p
d
f
# of
orbitals
1
3
5
7
Max # of
electrons
2
6
10
14
Electrons
2
3s
Sublevel
Electron Configuration

The ways in which electrons are arranged around the
nuclei of atoms.
HINT: You must include the Neighborhood,
Street, and House.
Example:
Aluminum –
ATTENTION!!!
Three Laws You Must Follow In Order
to Master Electron Configuration
Law 1: Aufbau Principle
 Electrons
enter
orbitals of
lowest energy
first
Law 2: Pauli Exclusion Principle
1.
Each orbital holds up to two electrons

“Two to a seat!”
2. The electrons in those “pairs” have to
spin in opposite directions
Law 3: Hund’s Rule
2p
 Electrons
 Then

fill orbitals with the same spin first
they “buddy up”
Because if you could have a seat to yourself, you’d take that
before having to cram in with someone else! Right?
How do we find valence electrons?
Look at the highest energy level
Count the number of electrons in this level
Example:
Aluminum –
3 valence
electrons
3rd Energy Level
Steps for Orbital notation
1.
Find the element on the periodic table to know
how many electrons you have
2.
Use Aufbau Principle (the tree diagram) to
determine which sublevels you fill first
3.
Place electrons in the sublevels using the 3 Laws
from today
4.
Continue until all electrons have been placed
You will need your Periodic Table
1
1
IA
1
H
Periodic Table
2
IIA
13
IIIA
14
IVA
15
VA
16
VIA
17
VIIA
1.00797
2
3
Li
4
5
Be
B
6.939 9.0122
3
4
5
6
7
11
Na
12
Mg
22.9898 24.305
19
20
K
Ca
3
IIIB
21
Sc
4
IVB
22
Ti
5
VB
23
V
6
VIB
24
Cr
7
VIIB
25
Mn
Rb
Sr
Mo
Tc
85.47
55
87.62 88.905 91.22 92.906 95.94
56
57
72
73
74
[99]
75
Ba
7
N
8
O
9
F
He
4.0026
10
Ne
10.811 12.0112 14.0067 15.9994 18.9984 20.179
8
26
Fe
9
VIIIB
27
Co
10
28
Ni
39.102 40.08 44.956 47.90 50.942 51.996 54.9380 55.847 58.9332 58.71
37
38
39
40
41
42
43
44
45
46
Cs
6
C
18
VIIIA
2
Y
La
Zr
Hf
Nb
Ta
W
Re
132.905 137.34 138.91 178.49 180.948 183.85 186.2
87
88
89
104
105
106
107
Fr
Ra
Ac
Ku
[223]
[226]
[227]
[260]
Ru
Rh
Pd
11
IB
29
12
IIB
30
Cu
Zn
63.54
47
65.37
48
Ag
Cd
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
26.9815 28.086 30.9738 32.064 35.453 39.948
31
32
33
34
35
36
Ga
Ge
65.37
49
72.59 74.9216 78.96 79.909 83.80
50
51
52
53
54
In
Sn
As
Sb
Se
Te
Br
I
Kr
Xe
101.07 102.905 106.4 107.870 112.40 114.82 118.69 121.75 127.60 126.904 131.30
76
77
78
79
80
81
82
83
84
85
86
Os
190.2
108
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
192.2 195.09 196.967 200.59 204.37 207.19 208.980 [210]
109
At
Rn
[210]
[222]
Example (1)
Lithium
Example (2)
Aluminum
Example (3)
Vanadium
Guided Practice
1.
Compose the FULL orbital notation for
Nitrogen and based on the orbital notation,
write the number of valence electrons in the
box
2.
Compose the FULL orbital notation for
Calcium and based on the orbital notation,
write the number of valence electrons in the
box
3.
Compose the FULL orbital notation for Cobalt
and based on the orbital notation, write the
number of valence electrons in the box
Work… Work… Work…
Spend the remainder of class practicing
Electron Configuration
Closing
 How
many electrons can be held in an
orbital?
 What
will help you fill the electrons in
the correct order?
Warm Up: 4 Minutes
Stay in your own seat
Write the Learning
Target
You should be working SILENTLY
Construct the Orbital Notation Electron
Configuration for Titanium
Agenda
 Warm
up: 8 Minutes
 Expectations
 Quiz:
for Quiz: 5 Minutes
30 Minutes
 Closing:
2 Minutes
Goals for Assessment
85%
13 Questions
Topics Covered
 Atomic
Theory Scientist
 Electromagnetic
 Speed
Spectrum
of Light Formula
 Energy
Formula
 Atomic
Mass Calculations (Isotopes)
 Orbital
Notation Electron Configuration
Clear your desks
Clear desk of everything except
for a pencil/pen and calculator
Backpacks, binders, and notes on
the FLOOR
Testing Tips

Read the problem and answer choices CAREFULLY

If you don’t know the answer, make sure you at least take a
guess

Guessing on questions you don’t know can only help you!
All formulas and constants you
need are in the quiz packet
Quiz Rules

Students will remain SILENT for the duration of the quiz.
Even if you are done, YOU CANNOT TALK

Keep your eyes on YOUR OWN PAPER
Failure to follow the testing rules will result in your quiz
being taken. You will then receive a ZERO and a dean
referral.
Expectations for Assessment
Silence
Desk Cleared [Except A Pencil & A
Calculator
Focused mind
When you are finished, see Mr. Ghosh for Orbital Notation
Electron Configuration Practice
Closing

Do you feel like you did well on your quiz?

What can you do differently to improve your
performance?