A. Visit the Gas Laws web site and answer the following questions:
1. State the four variables that are commonly
used to quantify a gas.
Variable | |
Name | Symbol |
2. State the following gas laws in equation form using the above symbols
and give an example for each.
Law | Example | |
Boyle's law |
| |
Charles's law |
| |
Gay-Lussac's law |
|
B. Boyle's law: Pressure vs.
Volume
Equipment needed: PC, interface, pressure sensor, and syringe.
1) Connect the pressure sensor to analog channel A on the Interface.
2) Open DataStudio. Select “Open Activity”, select "Library", select Physics Labs, and open “P18 Boyle’s Law”.
3) Take the syringe, and pull out the piston to the 20 ml mark.
4) Line up the quick-release connector with the corresponding end of the pressure sensor. Push it in and turn it clockwise until you hear a small click.
5) Double click on the Volume and Pressure Table icon under the displays list on the left side of the screen.
6) Click on the Start button.
7) Check to make sure that the syringe position is still at 20 ml, and Click once on the Keep button.
8) Make sure that the corresponding syringe volume reads “20”. If it does not, click once on the box and type in the correct value.
9) Push the piston of the syringe until it reaches the 19 ml mark and click once again on the Keep button.
10) Again, change the corresponding syringe volume to 19.
11) Continue decreasing the volume by 1 ml and taking measurements each time until you reach 10 ml.
12) Click on the Stop button.
13) Double click
on the Volume vs. Pressure graph and examine it. Do the pressure and volume seem
to be directly or inversely proportional?
Does this agree with Boyle’s
Law?
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14) Go back to the volume and pressure data table and high-light the volume column. (move the mouse arrow in the title cell and left-click). Click Edit and copy the volume column. Open a blank excel page and paste the volume data. Delete the time column.
15) Do the same as 14 for the pressure column.
16) Close the Data Studio window, without saving.
17) In the Excel page, create two more columns, one for 1/V and the other for PV and plot P versus 1/V. Does your results verify Boyle's law?
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18) What are possible sources of error or limitations in this experiment? Include some suggestions for improvement.
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C. Gay-Lussac's law: Pressure versus Temperature
Purpose: To investigate the relationship between the pressure of a gas and the temperature of a gas when its volume is kept constant and determine the value of the absolute zero temperature.
Apparatus: Pressure sensor, temperature sensor, PC w/interface, hot plate, beaker, stand w/clamp, flask with rubber stopper and connector, water, and ice.
Procedure:
1. Place the flask inside the beaker and fill the beaker with some ice & water mixture, and put the beaker on the hot plate. Do not turn on the hot plate now.
2. Attach the flask to the clamp of the stand so that it will be submerged in the ice-water mixture.
3. Connect the temperature sensor to analog channel A and place the probe in the ice-water mixture.
4. Connect the pressure sensor to analog channel B, and to the connector-tube that connects to the flask.
5. Open "DataStudio", select "Open Activity", select "Library", select "Physics Labs", and select P17, Pressure versus Temperature.
6. Click on the Pressure and Temperature Table display, and click "Start".
7. After stirring the ice-water mixture, click "Keep" to collect the first temperature and pressure data.
8. Turn on the hot-plate, and watch the temperature while stirring.
9. When the temperature reaches about 8-9 degrees, stir the water well, and click "Keep" to collect the data again.
10. Continue collecting data,
about every 10 degree temperature change, and until the water boils. It is
important that you stir the water
for a minute before you click
keep.
11. Use the graph display to
determine whether or not the relationship between pressure and temperature is
linear.
Is the relationship between the pressure and temperature linear or
not?
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12. Click 'Fit' and select
'Linear' from the menu. Use the fit to estimate the value of absolute
zero.
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D. Charles's Law: Volume vs. Temperature
In order to verify Charles' law we will visit the following Java site. As you increase the temperature, the volume will increase and it will also fluctuate. We will collect three volume data and find the average volume. Set N= 30, P =30.
Temperature (K) | Volume-1 | Volume-2 | Volume-3 | Volume (mL) |
0 | ||||
50 | ||||
100 | ||||
150 | ||||
200 | ||||
250 | ||||
300 |
Plot Volume versus Temperature and describe how your results verify Charles's law.