AP Thermodynamics Review
Team Members: Kate O’Neill and Kiah Mattson
Date lesson will be taught: 4/12&14
Grade level: 11-12
Graphic Organizer:
Concepts:
Calorimetry
Laws of Thermodynamics
Thermodynamics of reaction
Objectives:
The student will be able to:
1. Perform calorimetry calculations
2. Evaluate the sources of error in the design of a calorimetry experiment
3. Explain the implications of the laws of thermodynamics for the energy and spontaneity of reactions
4. Calculate the entropy, enthalpy, and Gibbs free energy of reaction
5. Classify the spontaneity of a reaction based on the entropy, enthalpy, and Gibbs free energy.
Kansas Science and/or Mathematics Standards, Benchmarks, and Indicators:
SCIENCE AS INQUIRY – The student will develop the abilities necessary to do scientific inquiry and develop an
understanding of scientific inquiry.
Benchmark 1: The student will demonstrate the abilities necessary to do scientific inquiry.
STANDARD 2B: PHYSICS
PHYSICS – The student will develop an understanding of the structure of atoms, compounds, chemical reactions,
and the interactions of energy and matter.
Benchmark 2: The student will understand the conservation of mass and energy, and the First and Second Laws of
Thermodynamics.
STANDARD 6: SCIENCE IN PERSONAL AND ENVIRONMENTAL PERSPECTIVES
SCIENCE IN PERSONAL AND ENVIRONMENTAL PERSPECTIVES – The student will develop an understanding
of personal and community health, population growth, natural resources, environmental quality, natural and humaninduced hazards, and science and technology in local, national, and global settings.
Benchmark 1: The student will develop an understanding of the overall functioning of human systems and their
interaction with the environment in order to understand specific mechanisms and processes related to health issues.
Indicator 3: The student understands informed personal choices concerning fitness and health involve an understanding
of chemistry and biology.
Materials list, advance preparation, and handouts:
Marshmallows, peanuts, cheese puffs
Flint lighters
Burners
Evaporating dishes
Test tubes
Tongs
Gummy bear video
PowerPoint to walk through calculations
Accommodations:
By working in groups for the thermodynamic calculations of the gummy bear reaction, stronger students can
help those who are struggling. Reviewing the calculations in class can further help those students.
For lower performing students or those for whom writing is difficult, scaffold lab outlines could be provided.
If this lesson were being done in a standard level class, you might have high achieving students who want to do
more. They could predict the caloric values of the foods based on their fat/carbohydrate/protein content and/or
prepare a presentation on the implications of calorimetry for food choices.
Hopefully since this is a review, the terminology would be familiar to English Language Learners. We
discussed the definitions of the terms at the beginning so that should reinforce those words. Having students
work in groups means that if ELL’s are better at the calculations but don’t wan to explain it to the whole class,
they can elect someone else to present.
There was also limited writing necessary on the lab report and it was mostly answering fairly straightforward
questions. These questions could be typed up or dictated to someone else if necessary.
Safety:
Goggles and lab coats, hair tied back while burning assorted food items
Work over fireproof surfaces while burning food
Properly educate students on the use of gas burners in the lab
If you choose to actually perform the sucrose/potassium chlorate reaction, you need a hood / blast shield
Backup Plan: If the school has YouTube blocked, there is a version of this video on SchoolTube
It’s okay if the food doesn’t burn all the way (some of them don’t). It’s important to talk about what that means
for the error analysis at the end. If one of the foods does not burn well, we will have back up foods to burn. If
the students get done with the lab early, they will work on AP exam questions.
Five-E Plan
Teacher Does
Probing Questions
Critical questions that will
connect to prior knowledge
and create a need to know.
Student responses
Expected Student
Responses/Misconceptions
Gummy bear reaction (Just
the video. It’s dangerous)
Why is the reaction so
violent?
http://www.youtube.com/w
atch?v=txkRCIPSsjM
What makes it go?
The reaction is highly
exothermic because the
products are much more
stable than the reactants
Engage:
Learning Experience(s)
Time: __5____minutes
Can we do this in class?--No it is too dangerous.
Teacher Does
Explore:
Learning Experience(s)
Time: __30__minutes
Day 1:
Open up thermodynamics
power point (could not
attach to document but it is
on BB).
Have students define
enthalpy, entropy, and
Gibbs free energy in their
own words.
Probing Questions
Student responses
Critical questions that will
guide students to a common
set of experiences.
Expected Student
Responses/Misconceptions
What is entropy?
Entropy is the disorder in a
system.
Entropy of products minus
entropy of reactants.
∆S°=[∑nSproducts-
What is the equation for
finding entropy of a
reaction?
Entropy is the
thermodynamic property
Can it decrease?
that can be used to
determine the energy not
available for useful work in
a thermodynamic process.
It is defined by the second
law of thermodynamics,
which says that entropy of a
system always increases or
∑nSreactants]
No. Not in an isolated
system.
stays the same.
Enthalpy: Measure of total
energy in a thermodynamic
system.
What is enthalpy?
What is the equation for
enthalpy of a reaction?
Enthalpy is a measure of
energy.
Change in enthalpy equals
sum of enthalpies of
products minus sum of
enthalpies of reactants.
∆H°=[∑nHproducts∑nHreactants]
What is Gibbs free energy?
Gibbs Free Energy:
Measures useful work
obtainable from an isolated
system.
What is the equation for the
standard Gibbs free energy
of a reaction?
Assign each group to solve
for either enthalpy, entropy,
or Gibbs free energy for the
gummy bear reaction:
C12H22O11+8KClO3=12CO2
+11H2O+8KCl
Gibbs free energy is a
different measure of energy.
Change in Gibbs Free
energy equals the sum of the
Gibbs free energies of the
products minus the sum of
the Gibbs free energies of
the reactants.
∆G°=[∑nGproducts∑nGreactants]
Hand out the worksheet
with the enthalpies,
entropies, and Gibbs free
energies for each
compound.
Give the students ~5
minutes to work out the
problem in their groups.
Assign a spokesperson to
each group to go up to the
overhead and show the
class how they obtained
their answer.
Are there any questions
about these three energies?
How are they all related?
What is a calorie a measure
of?
How do you calculate the
heat energy in food?
How does calorimetry
work?
What does this mean for
diet?
Energy!
Show the last slide of the
powerpoint again to show
the students how the
energies are related.
Briefly discuss calorimetry
and the difference between
calories and Calories. A
food calorie is actually
1000 Calories or 1 kcal.
Distribute the lab handout.
Give the students ~1 minute
Calorimetry is how food
energy content is
calculated, by combusting
food under water.
Fats have higher caloric
value than carbohydrates
and proteins, which has
to read over the lab then see
if there are any questions.
Are there any questions?
implications for diet
Have the students write one
thing they learned and one
thing they still have a
question about after the
first day. After class read
their comments and provide
feedback.
Day 2:
In the classroom review the
instructions for the lab and
make sure students
understand calorimetry.
How will we be measuring
the energy of the food?
How is this a correct
Lead the students to the lab. measure of energy?
Make sure all students are
following proper safety
protocol.
The students will perform
the lab and the teacher will
facilitate and provide
helpful instruction as
needed.
Teacher Does
Probing Questions
By recording the change in
temperature of the water
above it.
Because the first law of
thermodynamics states that
energy cannot be created or
destroyed it can only be
transferred. Therefore, the
energy from the food
escapes in the form of heat
and is transferred to the
water.
Student responses
Critical questions that will
help students clarify their
understanding and
introduce information
related to the lesson
concepts/skills.
Expected Student
Responses/Misconceptions
Calculate the enthalpy,
Day 1:
The gummy bear reaction is entropy, and free energy of
C12H22O11+8KClO3=12CO2 reaction for this reaction
Students should be able to
calculate and interpret
these values using
Explain:
Learning Experience(s)
Time: ______minutes
+11H2O+8KCl
Is this a spontaneous
reaction? Why not?
Day 2:
See lab and lab discussion
Teacher Does
Extend / Elaborate:
Learning Experience(s)
Time: ______minutes
Go through the
calculations for the
calorimetry lab
Discuss error
Teacher Does
Evaluate:
Include summative
evaluation below.
Time: __5___minutes
Day 1: worksheets w/
thermodynamic
calculations and name
tents.
Day 2: lab report and name
tents.
Probing Questions
formation values.
Yes. Because they react
without the need for heat.
Because the Gibbs free
energy is
Student responses
Critical questions that will
help students extend or
apply their newly acquired
concepts/skills in new
situations.
Expected Student
Responses/Misconceptions
How much energy is in the
food based on the change in
temperature of water in a
calorimeter?
Maybe compare that to
energy needed to do a task
Evaluate sources of error
The apparatus we used is
not covered or contained, so
heat could readily escape
into the air.
Probing Questions
Did the students remember
or determine how to
calculate the
thermodynamics of the
gummy bear reaction?
Did the students accurately
evaluate the reason for the
caloric difference between
different foods?
Did the students accurate
assess the sources of error
for the lab procedure used?
Student responses
Expected Student
Outcomes
The students quickly
remembered how to
calculate thermodynamics
of reaction
The students mistakenly
believed that the caloric
density of food was affected
by the amount of air in the
food, rather than the ratio of
fat to carbohydrates/proteins
The students effectively
assessed the sources of error
as being the lack of
isolation of the calorimeter
The calorimetry lab is attached but it was a .pdf file and I could not figure out how to put it in here as an
icon. Sorry!