Heat (Thermo) Unit
March 14- March 24 (2016)
Day 1: Boiling Water Lab
Objectives (SWBAT):
Physical Science 43- Graph the energy changes that occur when a substance, such as water, goes from a solid to a liquid
state, and then to a gaseous state
Physical Science 44- Measure and graph energy changes during chemical reactions observed in the laboratory
Inquiry 5- Use graphing skills to solve problems
Evaluated by:
Boiling Water Lab
Class structure:
Do Now: Make a hypothesis for today’s lab then read through the procedure as the hypothesis is stamped.
1.
2.
3.
4.
Engage- The class will review the safety precautions and procedure for the day’s lab.
Explore- Students will collect data and record values for temperature as their ice melts then boils.
Explain- Students will graph their data.
Elaborate- Students will explain why some portions of the graph were flat in terms of data collection and
observations made. Students will then compare the length of the first flat line to the second flat line
while teacher introduces the vocabulary terms for these lines- heat of fusion and heat of vaporization.
Summary: Energy must be input as heat to change a substance from a solid to a liquid (remember KMT). This energy is
called the heat of fusion. More energy must be put in to convert liquid to vapor, called heat of vaporization.
Day 2: Heat of Phase Change Calculations
Objectives (SWBAT):
Physical Science 31- Describe chemical changes and reactions using diagrams and descriptions of the reactants,
products, and energy change
Physical Science 43- Graph and compute the energy changes that occur when a substance, such as water, goes from a
solid to a liquid state, and then to a gaseous state
Inquiry 5- Use mathematics to solve problems
Evaluated by:
Heat of Phase Change Calculations
Class structure:
Do Now: Which two phase changes would be associated with heat of fusion? With heat of vaporization?
1. Engage- Teacher will use the Do Now to remind students of the reversibility of reactions then lead into
the need for a signal in the number to tell you whether the reaction is, for example, solid to liquid or
liquid to solid.
a. Vocabulary:
i. endothermic- heat must be put in/ absorbed for the reaction or phase change to happen,
has a (+) ΔH value, acts as a reactant in the equation (look back at Le Chatelier
worksheet to identify the endothermic reaction)
ii. exothermic- heat must be taken out/released for the reaction or phase change to
happen, has a (-) ΔH value, acts as a product in the equation (look back at Le Chatelier
worksheet to identify the endothermic reaction)
2. Explore- Students will look back at the Le Chatelier worksheet to identify two two reactions as endo or
exothermic then practice identifying endo and exothermic reactions through observation on the heat
transfer worksheet.
3. Explain- Students will explain their endo/exothermic identifications using explanations of heat flow then
explain vocabulary terms- latent heat and heat of fusion vs heat of vaporization based on their lab
experience from Day 1.
4. Elaborate- Students will calculate the amount of energy transferred during a phase change and apply the
correct sign to the number.
Summary: Phase changes require and input of energy (heat as a reactant) or release of energy (heat as a product). This
heat can be calculated using the substance’s constant multiplied by its mass. The heavier the substance, the more
energy required for a phase change.
Day 3: Heat of Temperature Change Calculations
Objectives (SWBAT):
Physical Science 30- Solve problems involving heat flow and temperature changes by using known values of specific heat
and latent heat of phase change
Inquiry 5- Use mathematics to solve problems
Evaluated by:
Heat of Temperature Change Calculations
Class structure:
Do Now: Why does a transfer of energy result in a temperature change (hint: what does it do to the particles/what is the
definition of temperature)?
1. Engage- Teacher will draw a heating curve on the board and students will come up to the board to label
all phases, phase changes, heat of fusion, heat of vaporization, and when the Q=ΔH*m equation can be
used. Then, the teacher will point out that only on the sloped lines (temperature changes) do we not
have an equation and give the equation (Q=C*m*ΔT).
2. Explore- Students will calculate the heat needed to raise the temperature of various substances.
3. Explain- Students will show all work.
4. Elaborate- Students will solve two and three part problems- phase and temperature changes- and show
all work.
Summary: Raising the temperature of a substance required increasing the kinetic energy of the particles. This energy
comes from an input of heat. The amount of heat needed depends on the material (each has a specific heat constant),
amount, and the temperature difference needed.
Day 4: Heating Curve Mini Quiz and Calorimetry Calculations
Objectives (SWBAT):
Physical Science 31- Describe chemical changes and reactions using diagrams and descriptions of the reactants,
products, and energy change
Physical Science 30- Solve problems involving heat flow and temperature changes by using known values of specific heat
and latent heat of phase change
Inquiry 5- Use mathematics to solve problems
Evaluated by:
-Heating Curve Mini Quiz
-Calorimetry Prelab
Class structure:
Do Now: Clear your desks for the Heating Curve Mini Quiz
1. Engage- Students will review the two equations with a practice problem:
Calculate the heat needed to raise 50g of water from 30°C to the boiling point, then boil it? Teacher will
introduce the idea that heat of a temperature change could be used for endo and exothermic chemical
reactions.
2. Explore- Students will read p. 562 and 563 in the textbook about coffee cup and bomb calorimeters.
3. Explain- Students will describe the two types of calorimeters, filling in the notes sheet.
4. Elaborate- Students will decipher calorimetry word problems to calculate the heat transfer in reactions.
Summary: Substances in a chemical reaction have their bonds broken (releasing energy) and form new bonds (using
energy). The extra heat released or additional heat needed is called the enthalpy or heat of reaction and can be
measured using calorimetry devices.
Day 5: Cheeto Lab
Objectives (SWBAT):
Physical Science 2- Differentiate between accuracy and precision and evaluate percent error
Physical Science 44- Measure energy changes during chemical reactions observed in the laboratory
Inquiry 5- Use mathematics to solve problems
Inquiry 4- Conduct an investigation that includes multiple trials and record, organize, and display data appropriately
Evaluated by:
Cheeto Lab
Class structure:
Do Now: If a food has a high number of calories what does this mean for the body of the person consuming it?
1. Engage- The class will review safety precautions and general procedures for the day’s lab then groups
will check their members for safety compliance.
2. Explore- Students will burn Cheetos and record data and observations for each trial.
3. Explain- Students will calculate the heat released by the burning cheeto, use this to determine the
number of calories in a serving size, then compare their answer to the manufacturer’s data.
4. Elaborate- Students will offer possible sources of error for the data using the notes from day 4 for
assistance.
Summary: Bomb calorimetry, as used in today’s lab to determine the number of calories in a snack, is only for
combustion reactions. In this type of calorimetry, the heat released when an object burns is transferred to another
medium, water, so that the measurement of temperature change is easier.
Day 6: ΔH on a Potential Energy Graph and in Calculations
Objectives (SWBAT):
Physical Science 31- Describe chemical changes and reactions using diagrams and descriptions of the reactants,
products, and energy change
Physical Science 30- Solve problems involving heat flow by using known values of heat of formation
Inquiry 5- Use mathematics and graphing skills to solve problems
Evaluated by:
Heat of Reaction Calculations
Class structure:
Do Now: Answer the first four questions on the day’s worksheet.
1. Engage- Teacher will introduce the term heat of reaction as the difference in energy between reactants
and products (Q5) and show how this definition and the graph can be used to determine whether a
reaction is endo or exothermic (Q6).
2. Explore- Students will finish the rest of the graphing questions with an unlabeled graph.
3. Explain- Teacher will show how this can be calculated without a graph but with heat of formation data.
4. Elaborate- Students will calculate the heat of reaction for various problems using heat of formation data
while showing all work.
Summary: Graphing information is a big part of science. This is something that is tested on the ACT, PLAN, exams, and
regular tests. Be able to read and create a reaction progress diagram (potential energy graph). The most important part
is locating the reactants and products. Then, the enthalpy (heat) of reaction can be calculated as energy of the products
– energy of reactants.
Day 7: Hess’ Law Practice
Objectives (SWBAT):
Physical Science 31- Describe chemical changes and reactions using diagrams and descriptions of the reactants,
products, and energy change
Physical Science 30- Solve problems involving heat flow by using Hess’ Law
Inquiry 5- Use mathematics to solve problems
Evaluated by:
Hess’ Law Practice
Class structure:
Do Now: What is the heat of reaction for the equation below?
2 H2 (g) + O2 (g)  2 H2O (g)
1. Engage- Teacher will explain Hess’ Law in terms of puzzle and complete 2-3 problems with students.
2. Explore- Students will complete the remaining Hess’ Law problems.
3. Explain- Students will show all work mathematically and with notes out to the side of each equation.
4. Elaborate- Students will complete the test review for further practice.
Summary: In a multistep reaction, all component steps are added together for the total heat of reaction. This process is
called Hess’ Law.
Day 8: Review for Heat Test
Objectives (SWBAT):
Inquiry 5- Use mathematics and graphing skills to solve problems
Physical Science 2- Differentiate between accuracy and precision and evaluate percent error
Physical Science 30- Solve problems involving heat flow by using Hess’ Law, known values of heat of formation, or known
values of specific heat and latent heat of phase change
Physical Science 31- Describe chemical changes and reactions using diagrams and descriptions of the reactants,
products, and energy change
Physical Science 43- Graph and compute the energy changes that occur when a substance, such as water, goes from a
solid to a liquid state, and then to a gaseous state
Physical Science 44- Measure energy changes during chemical reactions observed in the laboratory
Evaluated by:
Review for Heat Test
Class structure:
Do Now: Organize your binder for tomorrow’s check.
1.
2.
3.
4.
Engage- Teacher will review the list of study topics on the board with student suggestions.
Explore- Teacher will discuss the answers to the test review.
Explain- Teacher will show all work during the discussion of the review questions.
Elaborate- Teacher will also review vocabulary and test layout.
Summary: This test is over chapter 17 if further assistance is needed. Be sure to come prepared tomorrow. We
are nearing the end but we are not quite there yet.
Day 9: Heat Test
Objectives (SWBAT):
Demonstrate at least 67 % proficiency on the standards of this unit
Evaluated by:
Test- Heat
Class structure:
Do Now: Take out a calculator and something to write with, open your binder to the table of contents and place
it on the back bench, move your bags to the A/C, and clear your calculator RAM
TEST
Summary: There are only 7 more weeks of school. One week is finals, one is review, so only five more of new material.
Work to solidify this material in your head as we go so that you will not have to study it 6 weeks from now to prepare.
Testing Preparation
GLE
Objective
Day(s) Addressed
Inquiry 5
Utilize mathematics, organizational tools, and graphing skills to solve problems
1-8
Physical
Science 2
Differentiate between accuracy and precision and evaluate percent error
5
Physical
Science 30
Solve problems involving heat flow by using Hess’ Law, known values of heat of
formation, or known values of specific heat and latent heat of phase change
3, 4, 6, 7
Physical
Science 31
Describe chemical changes and reactions using diagrams and descriptions of the
reactants, products, and energy change
2, 4, 6, 7
Physical
Science 43
Physical
Science 44
Graph and compute the energy changes that occur when a substance, such as
water, goes from a solid to a liquid state, and then to a gaseous state
Measure energy changes during chemical reactions observed in the laboratory
1, 2
1, 5
Vocabulary
Latent Heat
Exothermic
Heat of Reaction
Heat of Fusion
Calorimetry
Heat of Formation
Heat of Vaporization
Bomb Calorimeter
Hess’ Law
Endothermic
Coffee Cup Calorimeter
Equations
Q= ΔH*m
Q= C*m*ΔT
Assessment Design
Basic: 6 Questions
ΔHrxn= ΔHf (products)- ΔHf (reactants)
Standard: 12 Questions
% error = actual/theoretical *100
Expanded: 6 Questions
Essential Skills and Learning Objectives
Type of
Question
(MC, CR, P)
Basic
(Remember &
Understand)
Standard
(Apply &
Analyze)
Expanded
(Evaluate &
Create)
Solve heat of reaction problems using Hess’ Law or known
values of heat of formation
MC/CR
1 MC
1 CR
1 MC
2 CR
1 CR
Graph and compute the energy changes that occur when a
substance, such as water, goes from a solid to a liquid state,
and then to a gaseous state
MC/CR
2 MC
1 MC
5 CR
1 MC
3 CR
Describe chemical changes and reactions using diagrams
and descriptions of the reactants, products, and energy
change
MC/CR
1 MC
1 CR
1 MC
2 CR
1 CR