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Specific Heat Capacity
Lesson Plan
Prepared By:
Koh Chia Ho, Jared
054554L23
S7904178E
Lecturer: Dr Yap
Submission Date: 17 Oct 2005
Specific Heat Capacity
Topic: Thermal Properties of Matter
Subtopics: Specific Heat Capacity
Duration: 2 periods (70 minutes)
Level: Secondary 3 Express (Pure Physics)
Venue: Physics Laboratory
Lesson Prerequisites:
Students have learnt:
a) A rise in average kinetic energy of molecules in a substance corresponds to a rise in its
temperature.
b) Thermal energy is transferred from a region of higher temperature to a region of lower
temperature.
c) The motions of particles of substances in the three phases in terms of Brownian motion.
d) The Principle of Conservation of energy in the case of heating where the amount of heat energy
supplied to a substance is equal to the amount of heat energy gained by it.
Specific Instructional Objectives for the Lesson:
At the end of the lesson, students should be able to:
a) Define the terms heat capacity and specific heat capacity.
b) Recall the relationship thermal energy = mass specific heat capacity change in temperature
c) Apply the relationship between thermal energy, mass, specific heat capacity and change in
temperature to new situations or to solve related problems
d) Apply their knowledge of the high heat capacity of water to everyday applications.
Learning Aids & Resources:
Non IT: i) 1 metal spoon
ii) 1 plastic spoon
iii) 1 candle
iv) 1 balloon filled with air
v) 1 balloon half filled with water, half filled with air
vi) 1 beaker containing 400ml of water
vii) 1 beaker containing 400ml of cooking oil
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Specific Heat Capacity
viii) 2 immersion heaters
ix) Data logger with 2 temperature sensors
IT: i) PowerPoint Slides
ii) Java applet on colorimetry
Worksheet: Worksheet 1
New Concepts/Terms:
Heat capacity, specific heat capacity.
Concept Map:
Increases or decreases Heat absorbed or
Internal energy of matter
released, Q
Which in turn increases
or decreases
Potential energy Heat C Specific Heat
(due to Kinetic energy Capacity, C c Capacity, c
m
intermolecular (due to motion) Q C where m = mass Q mc
force)
Change in kinetic
energy causes Temperature change
in matter,
Set Induction and Use of Trigger Activity:
Demonstrate that despite students’ intuition, a heated water balloon does not burst due to the
high heat capacity of water.
Students will be rooting for the water balloon to burst and wetting the teacher in the process.
When this does not happen, it throws students into a cognitive disequilibrium. They would be
very interested to learn why, and as a result, be more attentive during the lesson.
Lesson Development:
1) Everyday applications
Stimulate students’ minds by recalling their past knowledge of heat insulators and conductors
and how it will be tied to heat capacity.
2) Use of IT - Interactive applet demonstration
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Specific Heat Capacity
Stimulate heating different amounts of water. As the science laboratory may not have
computers for students to use, this is done via teacher demonstration. An applet is used because
this activity is an intuitive concept that students may encounter in their daily lives. The applet is
able to produce precise readings that students need to perform calculations on later in the
lesson. Demonstration is done with guided questions to engage the students to think about the
topic. This also serves as a simple introduction to the concept of having different heat capacities
for different amounts of the same substance and sets the pace for the whole lesson. Later on,
students can revisit this applet to find the specific heat capacity of water.
3) Experimentation
Experimentation to investigate the different rates of heating between oil and water. This allows
students to observe first hand that for the same amount of heat supplied, different substances
show a different rise in temperature. They are then introduced to the definition of heat capacity.
Students can also appreciate the use of cooking oil in cooking because it has a low heat
capacity, so we are able to cook food faster.
If dataloggers are not available for all students they will have to use thermometers to record the
temperature. This also promotes data recording skills in the students.
4) Student participation in learning the definition and calculation of experimental results.
Through the use of scaffolding questions, students come up with the definition of heat capacity
and specific heat capacity themselves. This helps them to retain this new information better.
They then practice what they have learnt in doing some calculations based on their experimental
results. This helps give meaning to why they were asked to perform the experiment.
Lesson Closure:
Ask students to provide an answer to the induction activity performed at the beginning of class
based on what they had just learnt. This shows whether students understood the lesson.
Use of a concept map to see how what they had learnt fits into the whole picture. This is followed
by a quick summary, and students are asked to do some homework questions before the next
lesson.
Reference:
1) GCE ‘O’ Levels Physics Syllabus (5052)
2) C. Chew, Leong S.C., Chow S.F. (2000) Physics A Course for ‘O’ Level (2nd ed). Singapore:
Times Media Private Limited
3) Calorimetry Applet
http://www.chm.davidson.edu/java/calorimetry/calorimetry.html
4) Physics Lesson Plan for Thermal Properties of Matter Set E
http://teachersportal.nie.edu.sg/kcyap/Physics2002/O%20Level/Thermal%20Properties%20of%
20Matter/Set%20E%20-
%20Specific%20Heat%20Capacity/Specific%20Heat%20Capacity%20-
%20Lesson%20Plan%20(Set%20E).doc
5) UW Physics Lecture Demonstrations – Heat capacity of a water balloon
http://www.phys.washington.edu/facilities/lectdemo/thermo.html#cap
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Specific Heat Capacity
Lesson Plan
Stages Activities/Procedures Resources Rationale
Set Induction- Show a balloon filled with air, and a balloon half- 1 balloon filled Generate interest in
Demo filled with water to the students. with air the topic by
Ask students what they would expect if the balloon 1 balloon half- showing a
5 min filled with air is heated by the lighted candle. filled with water, demonstration.
Expect students to say the balloon will burst. half-filled with air Students will be
Demonstrate that the balloon will burst by bringing 1 lighted candle hoping the water
it near the lighter from the top. balloon bursts thus
Next, show students the balloon half-filled with PowerPoint wetting the teacher,
water and ask them the same question. Slides but that will not
Expect a mixture of answers: some say it will burst, happen.
some will say it will not.
Bring the balloon towards the lighter from the top Only give the
slowly making sure the flame does not touch the answer at the end
sides of the balloon, just the bottom. Show that the so that they will be
balloon does not burst. attentive during the
Ask students to think about the reasons why the lesson.
balloon does not burst. Feeling the
Tell the students that at the end of the lesson, they difference
will be able to answer the question. themselves creates
a lasting
Recall previous knowledge impression.
Show the plastic spoon and metal spoon to the
class. Let students recall
Ask students whether the spoons are at the same their previous
temperature. Plastic spoon knowledge of heat
Lead students to respond that both spoons are at Metal spoon conductors. Link
room temperature. the idea of heat
Touch the spoons one after another on most of the PowerPoint conductors and
students’ hands. Ask them whether they feel a Slides insulators to the
difference between the two materials. property of heat
Lead students to recall a concept they had capacity.
previously learnt – heat conductors and heat
insulators.
Lead students to explain the phenomenon they had
just experienced based on heat conductance – good
heat conductors conduct heat away from our skin
faster, making us feel cold.
Ask students what kind of material makes up the
frying pan’s handle and the actual pan itself.
Highlight that this is an application of heat
conductors and insulators.
Ask students why is it when the same amount of *Note:
heat is supplied to a conductor and an insulator, Microteaching
one becomes hotter than the other. Tell them that Segment
this is also another property that they are going to
learn.
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Specific Heat Capacity
Stages Activities/Procedures Resources Rationale
Introductory investigation
Lesson Show applet on calorimetry to students. Calorimetry An applet is used
Development 1- On the applet, heat up 20 ml of water, power applet. in this case because
Demo and 100W, for 10 sec and ask students what is the it stimulates the
introduction of temperature rise (7.28 degrees Celsius). heating process
concept of heat Ask students what they would expect if we double Worksheet faster than actually
capacity the amount of water to be heated, all else remain performing the
the same. Lead students to intuitively guess that PowerPoint experiment.
10 min they expect a lower temperature rise. Show that Slides Moreover this
their guess is correct via the applet (4.52 degrees property is intuitive
Celsius raise). so there is no need
Remind students to fill in the readings in the applet to perform the
into the worksheet actual experiment.
Explain to students that when we supply the same
amount of heat to different amounts of water, the Start with learning
temperature rise is different. This is because a about different heat
larger volume of water can absorb more heat before capacities between
raising its temperature – it has a larger heat different
capacity. substances first.
Explain the literal meaning of heat capacity so that This is followed by
students can remember easier. learning about
Ask students whether for same amounts of different heat
different substances, they have the same capacities between
temperature rise for the same heat supplied? Make different amounts
a guess. of the same
substance.
*Note:
Microteaching
Segment
Lesson Group students to work in pairs, each student will 1 beaker Reinforce the
Development 2- record the temperature of his own beaker of water containing 400 ml concept of heat
Reinforcement or oil. of water capacity by heating
of heat capacity Students are to heat 1 beaker of water (400ml) and 1 beaker different kinds of
and derive its 1 beaker of cooking oil (400ml) using an containing 400 ml liquids.
definition. immersion heater. of cooking oil
Using temperature sensors connected to datalogger, 2 100 W Show the
20 min students are to observe the difference in heating immersion properties of heat
curves. If data loggers are not available, replace heaters capacity first
with thermometers. Students are to record down the 2 temperature before introducing
temperature every 30 seconds. sensors connected the definition and
Remind students to write down the readings in their to datalogger* formula.
worksheet with the correct units.
Show students that for the same amount of heat Worksheet Deriving the
supplied, the rise in temperature is different. definition based on
Tell the students they have just observed some PowerPoint their observations
properties of heat capacity of matter. Slides help them to recall
Derive the definition of heat capacity together with easier.
the students and show the formula. Fill in the
definition inside the worksheet: the amount of
energy needed to raise the temperature of a *normal mercury-
substance by 1 K. in-glass
Together with students, derive the unit for heat thermometers
capacity from the definition. may be used if
Highlight that the process of heat absorption is there are
reversible – the amount of heat lost during cooling insufficient data
is the same as the amount of heat gained for the loggers for
same change in temperature. students.
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Specific Heat Capacity
Stages Activities/Procedures Resources Rationale
Lesson Ask students to practice doing some questions on Worksheet Applying the
Development 3- the worksheet. formula to values
Application of Explain to students that the calorimeter in the PowerPoint they recorded
formula applet, and the beaker in the demo also absorbs Slides themselves gives
heat. Give them the heat capacity of the calorimeter students a greater
10 min as 53.64J/K. White Board sense of closeness
Ask students to apply the formula to calculate the to the lesson.
heat capacity of water in the applet.
Teacher to walk around helping students who
encountered difficulties with their calculations.
Lesson Explain that since the heat capacity of a substance Worksheet Lead students to
Development 3- is dependent on the amount of substance, it is more realize by
Extension of convenient to consider the heat capacity per unit PowerPoint themselves that the
formula to mass. Slides specific heat
specific heat Ask students to divide the heat capacities of water capacity is a
capacity obtained from the applet and from the demo by its White Board constant for the
respective masses. Remind students that the density same substance.
15 min of water is 1 g/cm3, so its mass in grams Deriving the
correspond to its volume in cm3. specific heat
Ask them what they observe between the two capacity formula
values. They should get roughly the same values; from heat capacity
any variance could be due to experimental errors. helps students to
From their calculations, explain to students that the link concepts
heat capacity of 1 g of the same substance (in this together.
case water) is always the same. This is called its
specific heat capacity and they have just calculated
the specific heat capacity of water.
Define specific heat capacity by extending the heat
capacity formula; divide heat capacity by its mass.
Remind students that because the specific heat
capacity of a substance is a constant, it is more
meaningful and it is more commonly used than
heat capacity.
Ask students to practice some questions on the
worksheet. Teacher to go through the thinking
process with students, providing guidance and
scaffolding.
Highlight the differences between heat capacity
and specific heat capacity in terms of definition and
SI unit.
Remind students of the naming conventions: C for
heat capacity, c for specific heat capacity.
Lesson Ask students what applications they can think of Worksheet Let students
Development 4 based on the high specific heat capacity of water. PowerPoint understand the
Applications Teacher to lead students where necessary. Slides usefulness of heat
Some applications: capacity.
5 min 1. Hot water bottle to keep warm on cold nights. White Board
2. Water used as cooling liquid in car engines
3. Land and Sea breezes.
Closure Remind students of the demonstration done at the PowerPoint Provide a summary
beginning of the lesson, and ask students to explain Slides for the lesson and
5 min why the balloon does not burst based on what they check whether the
had learnt on heat capacity: (1) balloon is stretched White Board students are able to
very thin there is good thermal contact between understand the
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Specific Heat Capacity
Stages Activities/Procedures Resources Rationale
water and flame. (2) due to the high heat capacity concept.
of water, heat is quickly absorbed and the rubber
does not get heated enough to melt.
Remind students to realize that water has a high
specific heat capacity.
Remind students that heat insulators have very high
specific heat capacity so they do not get hot easily.
Check for understanding by asking students that
they have learnt in the lesson.
Recap using a concept map.
Answer any queries students may have on the
topic.
Ask students to do some exercises on heat capacity
at the end of the worksheet.
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