GRADE 10 SCIENCE
Bringing the Greenhouse Effect Down to Earth
Curriculum Expectations
CHV.02D
CHV.03D
CH2.01D
CH2.06D
CH2.07D
CH2.13D
CH3.01D
CH3.02D
ESV.01D
ESV.02D
ESV.03D
ES2.01D
SNC 2D Chemistry: Chemical Process
Overall Expectations
Design and conduct investigations of chemical reactions using standard scientific
procedures, and communicate the results.
Determine why knowledge of chemical reactions is important in developing
consumer products and industrial processes and in addressing environmental
concerns.
Developing Skills of Inquiry and Communication
Through investigations and applications of basic concepts, select and use
appropriate apparatus, and apply WHMIS safety procedures for the handling,
storage, disposal and recycling of laboratory materials (e.g., wear safety goggles
and aprons; use proper techniques for the handling, disposal and recycling of
acids, bases and heavy metal ions; describe procedures to be followed in an
emergency).
Through investigations and applications of basic concepts, describe experimental
procedures in the form of a laboratory report (e.g., clearly identify the variable
under investigation as well as the variables controlled; clearly describe the
procedures followed and the data obtained; write an analysis of what was learned
from the data).
Through investigations and applications of basic concepts, select and use
appropriate vocabulary, SI units and numeric, symbolic, graphic and linguistic
modes of representation to communicate scientific ideas, plans, results and
conclusions (e.g., descriptions of experimental procedures using the scientific
method; data presented in tables).
Conduct appropriate chemical tests to identify common gases (e.g., oxygen,
hydrogen, carbon dioxide).
Relating Science to Technology, Society and the Environment
Explain how environmental challenges can be addressed through an
understanding of chemical substances (e.g., challenges such as the renewal of the
Great Lakes, the neutralization of acid spills, the scrubbing of waste gases in
smokestacks).
Describe how an understanding of chemical reactions has led to the development
of new consumer products and technological processes (e.g., antacids, fireretardant materials).
SNC 2D Earth and Space Science: Weather Dynamics
Overall Expectations
Demonstrate an understanding of the factors affecting the fundamental processes
of weather systems.
Investigate and analyse trends in local and global weather conditions to forecast
local and global weather patterns.
Evaluate how technology has contributed to our understanding of the physical
factors that affect the weather.
Developing Skills of Inquiry and Communication
Through investigations and applications of basic concepts, formulate scientific
questions about weather-related phenomena, problems and issues (e.g., What is
the effect of heat energy transfer within the hydrosphere?).
BRINGING THE GREENHOUSE EFFECT DOWN TO EARTH
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ES2.04D
ES2.05D
ES2.06D
ES3.01D
CHV.03P
CH1.06P
CH3.02P
ES1.04P
ES1.05P
ES2.01P
ES2.02P
ES3.01P
Through investigations and applications of basic concepts, analyse data and
information and evaluate evidence and sources of information, identifying flaws
such as errors and bias (e.g., explain possible sources of error when interpreting a
satellite picture used for predicting weather).
Through investigations and applications of basic concepts, select and use
appropriate vocabulary and numeric, symbolic, graphic and linguistic modes of
representation to communicate scientific ideas, plans, results and conclusions
(e.g., use historical and current weather data to support a position on future
weather patterns).
Investigate factors which affect the development, severity and movement of
global and local weather systems (e.g., the ozone layer, El Niño, bodies of water,
glaciers, smog, rain forests).
Relating Science to Technology, Society and the Environment
Explain the role of weather dynamics in environmental phenomena and consider
the consequences to humans of changes in weather (e.g., the role of weather in air
pollution, acid rain, global warming and smog; the fact that smog aggravates
asthma).
SNC 2P Chemistry: Chemical Reactions and Their Practical Applications
Overall Expectations
Demonstrate an understanding of how chemical reactions relate to technological
products and processes commonly encountered in everyday life.
Understanding Basic Concepts
Demonstrate an understanding of neutralization through investigation of simple
acid-base reactions.
Relating Science to Technology, Society and the Environment
Investigate applications of acid-base reactions in common products and processes
(e.g., compare the effectiveness of different brands of antacid tablets by
quantitative analysis; prepare soap from lard and sodium hydroxide and compare
its lather formation with that of commercial soaps).
SNC 2P Earth and Space Science: Weather Systems
Understanding Basic Concepts
Observe, through experiment and simulation, and describe (a) the effects of
atmospheric pressure, (b) the pattern of air movement in convection, (c) the
phenomenon of inversion, (d) the greenhouse effect, and (e) heat transfer through
radiation (e.g., (a) the reduction of the boiling point of water with reduced
pressure or altitude; (c) the formation of dew or frost early in the morning
following a clear calm night; (e) the use of dark solar panels for effective heat
transfer).
Describe the factors relating to the rotation of the Earth that cause the
movement of air masses and variations in the Earth’s temperature.
Developing Skills of Inquiry and Communication
Through investigations and applications of basic concepts, identify factors that
affect the development, severity and movement of local weather systems (e.g.,
microclimates in rural and urban areas, El Nino, bodies of water, frontal systems,
smog).
Through investigations and applications of basic concepts, formulate scientific
questions about these factors and outline experimental procedures for finding
answers.
Relating Science to Technology, Society and the Environment
Identify the impact of climate change on economic, social and environmental
conditions.
BRINGING THE GREENHOUSE EFFECT DOWN TO EARTH
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Teacher's Lab Notes
This lab compares the amount of carbon dioxide found in four different sources. To
compare the amount of carbon dioxide among the sources you may use either
bromothymol blue to determine the amount of carbon dioxide followed by a titration
or the CO2 probe may be used. The first method will provide an indirect quantitative
analysis of carbon dioxide while the second method will provide actual carbon
dioxide concentrations in the four sources.
The students will be filling balloons with pure carbon dioxide, exhaled air, and
ambient air. The teacher should fill the balloons with automobile exhaust. For safety
reasons, you should wear thick gloves to protect your hands from being burned. Fill
the balloons in an open area and when a slight breeze is blowing to keep the exhaust
gases away from your face. Place a balloon over the narrow end of a metal funnel
and place the wide end of the funnel over the exhaust pipe of a running car. When
inflated, the balloons should each be about 7.5 cm in diameter. It may be easier to
over inflate the balloon and then let a little gas escape. Twist and tie the balloon.
Repeat the procedure with the same coloured balloon until you have one for each lab
group.
For the Bromothymol Blue method the ambient air solution in vial A will not turn
yellow. The level of CO2 in ambient air is too low to be detected by bromothymol blue.
Students will need around 60 drops of the diluted ammonia to neutralize the
solution in vial D (vinegar-baking soda reaction). The other two vials should require
between 7 and 40 drops. Caution students to add the drops slowly and shake
solutions between drops so they can get a careful record of when the colour changes
back to the same colour blue as the control. Since the students will have to add a
relatively large amount of ammonia to the solution in vial D, the colour of this
sample may be affected by dilution. To equalize this effect, you can have students
add some water to the other samples to make the volume in each sample equal. This
is easiest to do if sample D is titrated last.
Purpose
To compare the amount of carbon dioxide (CO2) in four different sources of gases
(ambient air, exhaled air, car exhaust, pure CO2).
Hypothesis
Rank the sources of carbon dioxide from highest concentration to lowest
concentration.
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Method A: Bromothymol Blue Method
Materials (enough for each team of two or four students)
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4 different coloured balloons (or 4 labeled balloons)
4 twist-ties
100 mL vinegar
5 mL baking soda
Safety goggles for wear at all times
5 vials or test tubes
1 funnel
1 graduated cylinder
a marble-size piece of modeling clay
a narrow-necked bottle (the neck should be narrow enough for a balloon to fit
over it)
a dropper bottle of bromothymol blue indicator solution
a dropper bottle of dilute household ammonia (1 part ammonia to 50 parts
distilled water)
Procedure
1.
Add 15 mL of water and 10 drops of bromothymol blue indicator solution to
each vial or test tube. Label the vials A, B, C, D, and Control.
2.
Fill each balloon until it has a 7.5 cm diameter.
Sample A (Ambient Air) - Use a tire pump to inflate the balloon to the
required diameter. Twist the rubber neck of the balloon and fasten it shut with
a twist tie. The tie should be at least 1 cm from the opening of the balloon.
Record the colour of the balloon used for this sample.
Sample B (Human Exhalation) - Have one team member blow up a balloon
to the required diameter. Twist and tie the balloon, and record balloon colour.
Sample C (Automobile Exhaust) - Your teacher will supply you with this
balloon. Record the colour.
Sample D (Nearly pure CO2) - Put 100 mL of vinegar in the narrow-necked
bottle. Using a funnel, add 5 mL of baking soda. Let the mixture bubble for 3
seconds to drive the air out, then slip the balloon over the neck of the bottle.
Inflate the balloon to the proper diameter. Twist, tie, and record the colour.
BRINGING THE GREENHOUSE EFFECT DOWN TO EARTH
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3.
Soften the clay and wrap it around one end of the straw to make a small
airtight collar that will fit into the neck of a balloon. The collar should look like
a cone with the straw in its middle, and should be large enough to plug the
neck of the balloon.
4.
Pick up Balloon A. Keeping the tie on it, slip the balloon's neck over the clay
collar and hold it against the collar to make an airtight seal. Place the other
end of the straw into the vial of water and bromothymol blue labeled A. Have
another partner remove the tie on the balloon and slowly untwist the balloon.
Keeping the neck of the balloon pinched to control the flow of gas, gently
squeeze the balloon so the gas slowly bubbles through the solution.
5.
Repeat the same procedure with the other balloons and their respective vials.
In some cases, the bromothymol blue solution will change colour, from blue to
yellow, indicating the presence of carbonic acid formed from CO2.
6.
Analyze each of the samples by titrating them with drops of dilute ammonia.
Ammonia neutralizes the carbonic acid. The bromothymol blue will return to a
blue colour when all the acid has reacted. Add drops of ammonia to each of the
samples that turned yellow, carefully counting the number of drops needed
until they are about the same colour as your control. Record the results.
Observations
Air Source
Colour of Bromothymol
Blue after bubbling
Number of drops
of ammonia
Ambient Air
Exhaled Human Air
Car Exhaust
(nearly) Pure CO2
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Method B: CO2 Probe Method
Materials (enough for each team of two or four students)
•
•
•
•
•
•
•
•
4 different coloured balloons (or 4 labeled balloons)
4 twist-ties
100 mL vinegar
5 mL baking soda
Safety goggles for wear at all times
LabPro interface
Data Pro program
Vernier CO2 sensor
Procedure
Figure 1
1.
Plug the CO2 Gas Sensor into Channel 1 of the LabPro interface. Connect the
handheld to the LabPro using the interface cable. Firmly press in the cable
ends.
2.
Press the power button on the handheld to turn it on. To start Data Pro, tap
the Data Pro icon on the Applications screen. Choose New from the Data Pro
menu or tap
to reset the program.
BRINGING THE GREENHOUSE EFFECT DOWN TO EARTH
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3.
Set up the handheld and interface for a CO2 Gas Sensor.
a)
b)
c)
d)
e)
f)
If the handheld displays CO2 GAS (ppm) in CH 1, proceed directly to Step 4.
If it does not, continue with this step to set up your sensor manually.
On the Main screen, tap.
Tap to select Channel 1.
Press the Scroll buttons on the handheld to scroll through the list of
sensors.
Choose CO2 GAS (ppm) from the sensor menu.
Tap
to return to the Main screen.
4.
Place the shaft of the CO2 Gas Sensor in the opening of the balloon (CO2
container). See figure 1. Gently twist the stopper on the shaft of the CO2 Gas
Sensor into the container opening. Do not twist the shaft of the CO2 Gas
Sensor or you may damage it.
5.
Wait one minute, then tap
to begin data collection. Data will be collected
for 2†minutes (or until there is no change in the data registered).
6.
Record the concentration of CO2.
7.
Remove the CO2 Gas Sensor from the respiration container.
8.
Use a notebook or notepad to fan air across the openings in the probe shaft of
the CO2 Gas Sensor for 1 minute.
9.
Repeat the same procedure (steps 7 - 11) with the other balloons to determine
the concentration of CO2 in each sample.
Observations
Air Source
Carbon Dioxide Concentration
Ambient Air
Exhaled Human Air
Car Exhaust
(nearly) Pure CO2
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Analysis Questions
1.
2.
3.
4.
Identify the control. What is the purpose of the control?
Identify the dependent and independent variable.
For procedure A, explain why the ambient air sample did not turn yellow.
How did your results compare to your hypothesis? Explain any differences.
Making Connections
5.
6.
7.
8.
9.
Why is automobile exhaust a concern?
What ways could you reduce the amount of CO2 you create? How could a city
reduce the amount of CO2 they emit?
What's more important, to develop and adapt cars with a new fuel that's safe
for the environment or to improve public transportation systems?
Why might it be difficult for the public to start using an alternative source?
What alternative power sources could be used with cars?
Conclusion
References
This activity is used with the permission of Climate Protection Institute. CTI
publishes "Greenhouse Gazette" and other programs. To receive more information
about CTI and other activities, write and tell them what grade you teach at 5833
Balmoral Dr., Oakland, CA 94619. This activity appeared in The Science Teacher,
May 1989.
Vernier Software and Technology. 2002. Science with Handhelds.
Suggested Website for Support
New Scientist Special Report on Climate Change. November, 2005.
http://www.newscientist.com/channel/earth/climate-change/
CSIRO Atmospheric Research. May 2002. The Greenhouse Effect Information
Sheet. http://www.dar.csiro.au/publications/holper_2001b.html
One-tonne Challenge. Last updated 2005-11-04.
http://www.climatechange.gc.ca/onetonne/english/index.asp?pid=170
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