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Two datalogging experiments:
Expt 1 Simulation of global warming
Expt 2 Comparing CO2 given out by different
fuels
Note: These are presented as teacher demonstrations, so safety assumptions are implicit.
For student usage, safety concerns would need to be made clear.
Experiment
1
A
simulation of global warming
Heat up a sample of carbon dioxide in a plastic
bottle using a simple lamp. Compare the heating effect with ordinary
air. The results can be analysed best when obtained with a data
logger. This investigation could be extended further to include
water vapour or methane. Most science labs have a plentiful supply
of methane from the gas taps for Bunsen burners.
The picture above and the data
logging activity idea was obtained from the Dr Daq website. Dr Daq
is a very inexpensive data logging solution designed for the school
environment. Other experiment ideas for using data logging in the
classroom can be found on the Dr Daq website. Click
here
Equipment
Required
- Data logger connected to a PC or a graphical calculator
- Two temperature probes
- Two plastic pop (soda) bottles
- Two clamp stands, bosses and clamps
- Carbon dioxide (can be made from HCl on marble chips)
- Two heat lamps or flexible spotlights (at least 60W)
- Modelling clay ( e.g Plasticine TM)
Method
Fill a plastic pop bottle with carbon dioxide. You could use hydrochloric
acid on marble chips to generate the CO2. You might have
a gas bottle supply, or could use a fizzy water making machine (e.g.
Soda Stream TM).
Set up the apparatus as shown above.
Even over a small time period such as 6 minutes we were able to
get a difference of 10 degrees in temperature between the two samples.
View data as excel file
Experiment 2
Comparing the CO2 given out by different
fuels
The following experiment idea and data were obtained
from http://www.woodrow.org/teachers/esi/1998/p/energy/
.
The investigation was designed to find out which fuel produces
the most CO2. A prediction was made that anthracite would
produce the most CO2 because anthracite produces the
most heat per gram of fuel.
This was their procedure:
- Weigh each sample of coal.
- Place wire gauze on top of ring stand.
- Place Bunsen burner under ring stand.
- Attach rubber tubing to a funnel and position the funnel so
that it sits on the gauze.
- Attach the other end of the tubing to the arm of a conical flask.
- Place the carbon dioxide probe in the top of the flask.
Make sure that all connections are tight.
- Burn one sample of the coal under the funnel and collect data
for 10 minutes.
- Graph the data.
- Repeat this procedure for each the other samples of coal.
- (Notes: The flask needs to be aired out between each monitoring
of gas. Simply remove the probe for a few minutes.)
![[Setup of Student Lab]](setup1.jpg)
- Observation:
- Weight of each coal sample:
| Anthracite = 3.179g |
| Bituminous = 3.517g |
| Peat = 3.086g |
This was their conclusion
Based on our data, anthracite and peat emit the most CO2
into the atmosphere, although it appears that anthracite produces
more CO2 over a longer period of time. Peat
started out slower but at approx. 3 minutes it was at the same
level as anthracite. Our hypothesis was somewhat proven
correct, but we were surprised that peat produced the same level
of CO2 as anthracite.
Analysing results
Download data as an excel file
Their experiment uses very slightly different amounts of fuel.
How can we use mathematical methods to manipulate the data so
that the results are fair? Does this alter the conclusions drawn?
If we assume that the Bunsen burner was underneath the fuel
during the whole burning process then the Bunsen will also produce
CO2.
The 'control' results may have been for the Bunsen burner with
no fuel.
If we take away the CO2 from the Bunsen burner,
using a spreadsheet, does this now change our conclusions?
Can you repeat this experiment in your lab? Can you think of
ways of modifying or improving the method?
If you have not got a CO2 probe, could you
use lime-water to indicate levels of CO2?
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