Specific Heat – Land Versus Water
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Specific Heat – Land Versus Water
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Specific Heat – Land Versus Water
Introduction
Journals and Snapshots
The Snapshot button is used to capture the
screen.
The Journal is where snapshots are stored
and viewed.
The Share button is used to export
or print your journal to turn in your
work.
Each page of this lab that
contains the symbol
should be inserted into your
journal. After completing a
lab page with the snapshot
symbol, tap
(in the upper
right hand corner) to insert
the page into your journal.
Note: You may want to take a
snapshot of the first page of
this lab as a cover page for
your journal.
Specific Heat – Land Versus Water
Lab Challenge
• Imagine standing near a large warm lake at
night. If you stand 500m from the lake the
night-time air feels cool. As you approach
the lake the air starts to feel warmer.
Dipping your feet in the lake you find the
water is much warmer than the night-time
air. What's going on?
• What does the specific heat of water versus
land have to do with the differential heating
and cooling of water and sand?
• How different are water and sand in their
rates of heating and cooling?
Specific Heat – Land Versus Water
Background
• How quickly a substance heats up or cools down
compared to other substances in its environment is
determined by its specific heat.
• Specific heat is an intrinsic property of a substance
and is dependent on molecular structure and
phase. Substances that have strong intermolecular
attractions have higher specific heats and require
more energy to raise or lower the temperature of
the substance.
• Liquid water has strong intermolecular attractions
(hydrogen bonding) giving it a high specific heat.
The hydrogen bonds can absorb a lot of energy
before they break.
Specific Heat – Land Versus Water
Self-Check
1. How quickly a substance heats up or cools
down is called ________________.
a) temperature phase
b) bond energy
c) absorbent content
d) specific heat
e) chill factor
Specific Heat – Land Versus Water
...Background
• Specific heat is the amount of energy needed to
raise the temperature of 1 gram of a substance 1
Kelvin, and it is expressed in units of joules per
gram Kelvin (J/gK). Often, specific heat is expressed
using the Celsius scale (J/g°C).
• The specific heat of water, 4.186 J/g°C, is often
represented as a separate measure, the calorie.
• Liquid water's specific heat is one of the highest of
any substance. Liquid water requires more heat
energy to increase in temperature than almost any
other substance. Liquid water also can lose more
energy than most other substances before it drops
in temperature.
Specific Heat – Land Versus Water
Self-Check
2. The specific heat of water is also known as a(n)
____________.
a) calorie
b) heat unit
c) joule
d) energy budget
e) g/mL
Specific Heat – Land Versus Water
Safety
• Follow all standard laboratory safety procedures.
• Wear safety glasses or goggles.
• Keep water away from sensitive electronic
equipment.
• Use care when handling hot objects and keep
electrical wires away from the hot plate.
Specific Heat – Land Versus Water
Materials and Equipment
Collect all of these materials before beginning the lab.
Note: Part 1 and Part 2 of this lab can be done on two separate days.
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•
•
Part 1 Materials:
Stainless Steel Temperature
sensors (2)
Beakers, glass (2), 250-mL
Heat lamp or 150 W
incandescent lamp
Water, 200-mL
Sand, (200 g)
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•
•
•
•
•
•
•
•
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Part 2 Materials:
Scale or Mass Balance (1 per class)
Water, 400-mL
Beaker, glass, 500-mL
Small tripod, base, and rod, and utility clamp
Hot plate
Test tube, glass, 18 x 250-mm (large)
Disposable insulated cup (2) and lid
Tongs
Stirring rod
Safety glasses or goggles
Specific Heat – Land Versus Water
Sequencing Challenge – Part 1
A. Weigh out 200g of
sand and 200g of
water in separate
beakers.
B. Determine the rate
of heating and
cooling for sand and
water.
C. Determine the
total change in
temperature (∆ °C)
for the water and
sand.
D. Collect data on a
graph showing initial,
maximum, and minimum
temperatures for the
water and sand.
E. Heat the beakers for
15 minutes using a
bright light. Then let
them cool for 15
minutes.
The steps to the left are part of
the procedure for Part 1 of this
lab activity. They are not in the
right order. Determine the
correct sequence of the steps,
then take a snapshot of this
page.
Specific Heat – Land Versus Water
Sequencing Challenge – Part 2
A. Calculate the specific
heat of the sand, and
compare it to the
specific heat of water.
B. Pour the heated sand
into the calorimeter.
Record temperature data
until the mixture cools to
room temperature.
C. Make a calorimeter out
of two insulated cups, 70 g
of room temperature
water, and the second
temperature probe.
D. Fill a test tube with
sand and insert a
temperature probe in
the sand.
E. Heat the test tube of
sand by placing it in
boiling water. Record
temperatures for five
minutes.
The steps to the left are part of
the procedure for Part 2 of this
lab activity. They are not in the
right order. Determine the
correct sequence of the steps,
then take a snapshot of this
page.
Specific Heat – Land Versus Water
Procedure-Part 1 Heating/Cooling of Water and Sand
1. Connect two temperature sensors to your SPARK Science Learning System.
2. Note: The 1st sensor you plug in will appear in graphs as “Temperature1.” The 2nd
sensor you plug in will appear in graphs as “Temperature2.” Make sure to keep
track of which is which.
3. Measure 200g of sand in one beaker and 200g of water in another beaker.
4. Place the 1st temperature sensor (Temperature1) into the water.
5. Place the 2nd temperature sensor (Temperature2) into the sand. Place the tip of
the temperature sensor no more than 5 cm below the surface of the sand.
6. Place the heat lamp in a position so it will heat both beakers equally.
Specific Heat – Land Versus Water
Procedure-Part 1 Heating/Cooling of Water and Sand
Q1: Which substance do you predict will heat up faster -- the water or the sand?
Explain your prediction.
Specific Heat – Land Versus Water
Procedure-Part 1 Heating/Cooling of Water and Sand
Q2: Why is it important to heat both beakers equally?
Specific Heat – Land Versus Water
Procedure-Part 1 Heating/Cooling of Water and Sand
7. Start collecting data.
data!
Note: Tap
and then tap
After 30 seconds, turn the heat lamp on. Keep recording
to scale your graph as needed.
8. View the graphs on the next page. The top graph shows the 1st temperature
sensor you plugged in (Temperature1). The bottom graph shows the 2nd
temperature sensor you plugged in (Temperature2).
9. Turn the heat lamp off after 15 minutes. Keep recording data as the sand and
water begin to cool.
10.Collect data for 15 more minutes, then stop collecting data.
Specific Heat – Land Versus Water
Specific Heat – Land Versus Water
Analyze the Graphs
11. Select the region of heating for water.*
12. Use the
button to find the rate of heating for
water (slope of the line).*
13. Use the
button to label the slope value onto the
graph above the section of line you highlighted.
14. Select the region of cooling for water, and repeat
steps 12 and 13. (You can deselect the previous one
now.)
15. Repeat the above procedure for finding the rate of
heating and cooling for the sand.
16. When all four parts of the graphs are labeled, take a
snapshot
and save your work
.
* To Find the Slope for a
Portion of a Run of Data:
1. Tap
to open the tools
palette.
2. Tap
and then tap two
points on the data run.
3. Adjust using both
buttons and then tap
.
4. Tap
and select linear fit
then tap OK (m=slope).
• To Label the Slope on the
Graph:
1. Remember the m value,
and tap
.
2. Type the value of m and
press OK.
3. Take a snapshot of the
graph now.
Specific Heat – Land Versus Water
Analysis
1. What linear fit data represents the Rate of Cooling or the
Rate of Heating?
Specific Heat – Land Versus Water
Analysis
2. Calculate a ratio for the Rate of Heating (sand) compared to the Rate of
Heating (water).
3. Calculate a ratio for the Rate of Cooling (sand) compared to the Rate of
Cooling (water).
Specific Heat – Land Versus Water
Analysis
4. Consider the ratios of the rates of heating and cooling for sand to water. What
do these ratios tell you about the possible specific heat of sand compared to
the specific heat of water?
Specific Heat – Land Versus Water
Analysis
5. In this exploration, what was the independent variable, what was the
dependent variable, and what factors did you hold constant?
Specific Heat – Land Versus Water
Procedure-Part 2 Specific Heat of Sand
1. Fill the 500-mL beaker about ¾ full with water.
2. Place the beaker on the hot plate, and turn it on to
the highest setting.
3. Set up the tripod, base, and rod while you wait for
the water to boil. Fasten a utility clamp just above
the beaker.
4. Find and record the mass of an empty test tube. Fill
the test tube halfway with sand and mass it again.
The difference is the mass of the sand. Record the
mass in the text box to the right. You will need this
data on pg. 29.
Specific Heat – Land Versus Water
Procedure-Part 2 Specific Heat of Sand
Q3: Why is it important to determine the mass of the sand without the test tube?
(Hint: the relationship for heat exchange in matter is Q = mc ∆T, where Q is the
total amount of energy exchanged, m is mass, c is the specific heat, and ∆T is
the change in temperature.)
Specific Heat – Land Versus Water
Procedure-Part 2 Specific Heat of Sand
5. Insert Temperature Probe 1 into the middle of the sand in the
middle of the test tube.
6. Clamp the test tube in the 500-mL beaker of boiling water.
Make sure the sand in the test tube is below the water level.
Q4: Why is it important to keep the end of the temperature
probe away from the bottom or sides of the test tube?
Specific Heat – Land Versus Water
Collect Data
1. On the next page, tap
to start collecting data with Temperature
Probe 1 in the sand in the test tube.
2. To view only the current run of data, open the data run box and
deselect the previous run.
3. After 5 minutes, tap
to stop collecting data.
4. Resize the graph to show the entire data run.
5. Find the minimum and maximum temperatures of the sand: open the
Tools Palette and tap
and then
, and select Minimum and
Maximum and OK. Record these values where indicated on the next
page.
Specific Heat – Land Versus Water
Collect Data
6. Record the minimum and
maximum temperatures
below and save this page to
your journal. You will need
this data on pg. 29.
Specific Heat – Land Versus Water
Procedure-Part 2 Specific Heat of Sand
7. Make a calorimeter by nesting two disposable
insulated cups.
8. Fill the nested cup with 70 g of room-temperature
water. (Measure this precisely; don’t lose any.)
9. Insert Temperature Probe 2 into the calorimeter.
You can insert the probe through a small hole in
the cup’s lid, along with a stirring tool.
10.Tap
to find the initial temperature of this roomtemperature water. (graph on next page)
11.Lift the lid. Using tongs, grasp the heated test
tube and dump the heated sand into the insulated
cup. Replace the lid with the probe and continue
recording data.
Q5: What is the purpose of
nesting one cup inside
another?
Specific Heat – Land Versus Water
Collect Data
1. Gently stir the sandy water, recording the temperature until a maximum
temperature has been reached, and the temperature has decreased for a minute
or more.
2. Tap
to stop collecting data.
3. Record the minimum and maximum temperature of the water in the
table on the next page.
Specific Heat – Land Versus Water
Analysis
1. Below, record the mass 2. Below, record the mass of 3. Use Q = mcDT to find the
of the water from pg.
the sand from pg. 22, and
energy change (Q) of the
27, and the change in
find and record the
water. Show your work.
water temperature
change in temperature of
from data on pg. 28.
the sand from pg. 26.
Specific Heat – Land Versus Water
Analysis
4. Knowing the energy change (Qw)of the water, what can you use as the
energy change (Qs) of the sand? Why?
Specific Heat – Land Versus Water
Analysis
5. Use your previous data and csand = Qsand/(msandDTsand ) to find the specific heat of
the sand.
Specific Heat – Land Versus Water
Synthesis
1. Assume that the data you got for sand represents data for land in general. How
does the specific heat of sand compared to the specific heat of water relate to
the differential heating and cooling of land versus water?
Specific Heat – Land Versus Water
Synthesis
2. Explain how the proximity to a large body of water influences weather.
Provide an example.
Specific Heat – Land Versus Water
Multiple Choice
1. If water has a high specific heat, which of the
following would be true?
a) Water cools down rapidly.
b) Water retains heat for a long time.
c) Air over land located near water is warmer
during the night than inland locations.
d) It takes a lot of energy to heat water.
e) All of the above are true EXCEPT (a).
Specific Heat – Land Versus Water
Multiple Choice
2. Compared to a substance with a low specific
heat, a substance that has a high specific heat
__________.
a) requires more heat per gram to be added to it to
cause an increase in temperature
b) requires less heat per gram to be added to it to
cause an increase in temperature
c) requires the same amount of heat per gram to
be added to it to cause an increase in
temperature
d) has a larger mass
e) None of these is true.
Specific Heat – Land Versus Water
Multiple Choice
3. Water has a high specific heat because
__________.
a) it changes from a solid to a liquid phase at a
relatively high temperature
b) it has strong chemical bonds, particularly
hydrogen bonds, between molecules
c) it boils at 100 °C
d) it freezes at 0 °C
e) It can get very hot
Specific Heat – Land Versus Water
Multiple Choice
4. The high specific heat of water compared to that
of land results in __________.
a) the small range of temperatures in the oceans
compared to that on land
b) coastal climates that have smaller ranges of
temperature compared to those of inland
areas
c) the ability of large fresh water bodies to stay in
liquid phase when air temperatures drop
below 0 °C
d) All of these are true.
Specific Heat – Land Versus Water
Congratulations!
You have completed the lab.
Please remember to follow your teacher's instructions for cleaning-up and submitting
your lab.
Specific Heat – Land Versus Water
References
ALL IMAGES WERE TAKEN FROM PASCO DOCUMENTATION, PUBLIC DOMAIN CLIP ART, OR WIKIMEDIA
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