LAB 8: VIRTUAL GAS LAWS AND GRAPHING
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This lab does NOT require a lab report.
You will work by yourself for this lab.
I Introduction
Gases are difficult to experiment with: they are difficult to trap in their pure form,
they are difficult to store, and they are difficult to dispense and measure easily.
Fortunately, modern technology has given us a way to perform simple experiments on
gases without the expensive equipment or the risky, explosive-prone setups.
In this lab, you will use an Internet applet to perform simple experiments on gases by
varying the quantities of pressure, volume, moles, and temperature of an ideal,
virtual gas. After collecting data from the applet, you will then construct graphs using
the spreadsheet programs Excel or Graphical Analysis. From your graphs, you will then
conclude whether each of the quantities are directly related to each other, inversely
related to each other, or not related to each other.
Equipment and Reagents
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Internet-connected computer
! Warnings!
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None, although the program is slightly addicting and could possibly cause mild
seizures if you stare at the little balls long enough.
Procedure
1) Set up your lab notebook.
2) Open up Microsoft Excel and steer your favorite web browser (or Internet
Explorer) to the gas law simulator on our “Links” page or found directly at:
http://intro.chem.okstate.edu/1314F00/Laboratory/GLP.htm
Part 1: Boyle’s Law - Relating Pressure and Volume
3) In your spreadsheet, label the first two columns “Volume” and “Pressure”.
4) In the Simulator, click the “Pressure” button. This will allow you to vary the
other properties and measure the effect on pressure. Measure the pressure at 5
different volumes. Record the volumes and pressures in your spreadsheet and
in your lab notebook.
5) Create a graph in Excel using the Chart Wizard:
a) Highlight your data.
b) Choose “X-Y scatterplot”
c) Take it from there…
6) Sketch the created graph in your lab notebook and determine the relationship
between pressure and volume.
Try two variations of your graph:
1) Graph P vs. 1/V. Do this by creating another column in your spreadsheet:
a) Name your 3rd column “1/V”.
b) In the first cell, enter an equation to calculate 1/V (type “=1/(click the
cell that contains your Volume)”).
c) Create a new graph and sketch it on your data sheet.
2) Graph PV vs. V. See steps above.
Volume
P·V
Pressure
Pressure
Save your file in the “AP Chem” folder in the “Common” folder.
1/V
V
Part 2: Charles’ Law - Relating Temperature and Volume
8) In the Simulator, click the “Volume” button. This will
allow you to vary the other properties and measure
the effect on volume. Measure the volume at 5
different temperatures. Record the volumes and
temperatures in your spreadsheet and in your lab
notebook.
Volume
7) In a new spreadsheet, label the first two columns
“Temperature” and “Volume”.
Temperature
9) Create a graph in Excel, sketch the created graph in your lab notebook, and
determine the relationship between temperature and volume.
Part 3: Gay-Lussac’s Law - Relating Temperature and Pressure
11) In the Simulator, click the “Pressure” button.
This will allow you to vary the other
properties and measure the effect on
pressure. Measure the pressure at 5 different
temperatures. Record the pressures and
temperatures in your spreadsheet and in your
lab notebook.
Pressure
10) In a new spreadsheet, label the first two
columns “Temperature” and “Pressure”.
Temperature
12) Create a graph in Excel, sketch the created
graph in your lab notebook, and determine the relationship between
temperature and pressure.
Part 4: Avogadro’s Law - Relating Moles and Volume
14) In the Simulator, click the “Volume” button.
This will allow you to vary the other properties
and measure the effect on volume. Measure the
volume at 5 different moles. Record the moles
and volumes in your spreadsheet and in your lab
notebook.
15) Create a graph in Excel, sketch the created
graph in your lab notebook, and determine the
relationship between moles and volume.
Volume
13) In a new spreadsheet, label the first two
columns “moles” and “Volume”.
mols
Data and Calculations (to be recorded on your lab Data Sheet)
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Title and Purpose
Procedure
All data tables and graphs (should be 6 of each)
Type of relationship between each variable: Direct, Inverse, or None?
Generic equation for relationship:
 Use y = k∙x for direct (where y and x are variables and k is a constant)
 Use x∙y = k for inverse
 Use y = k for no relation
? Questions to Answer
1) If you doubled the pressure of a gas and kept its moles and temperature constant,
what would the volume of the gas do? What is a “real world” situation in which
this happens?
2) If you doubled the temperature of a gas and kept its moles and pressure constant,
what would happen to the volume of the gas? What is a “real world” situation in
which this happens?
3) If you doubled the temperature of a gas and kept its moles and volume constant,
what would happen to the pressure of the gas? What is a “real world” situation in
which this happens?
4) If you doubled the moles of a gas and kept its pressure and temperature constant,
what would happen to the volume of the gas? What is a “real world” situation in
which this happens?