GAS LAW ASSIGNMENT

This project will consist of four parts

  1. The note which covers the Gas Laws
  2. The data
  3. The project instructions
  4. Analysis and related questions

The Note: Gas Law Definitions & Equations

At sufficiently low pressures and high temperatures, all gases have been found to obey three simple laws. These laws relate the volume of a gas to the pressure of a gas to the temperature.

Boyle's Law
When the temperature is kept constant, the volume of a given mass of an ideal gas varies inversly with pressure to which the gas is subjected. In mathematical terms, the product of pressure X volume of a given mass of gas remains constant.

Charles' Law
At constant pressure, the volume of a given mass of gas varies directly with the absolute or Kelvin temperature. In mathematical termsthe volume equals a constant times the temperature in Kelven.

Equations for Bolyle's & Charles' Laws Click Here

Gay-Lussac's Law
At a constant volume, the pressure of a given mass of gas varies directly with the absolute temperature. In mathematical terms the pressuse divided by the absolute temperature equals a constant.

Dalton's Law of Partial Pressures
The total pressure of a gasesous mixture is equal to the sum of the partial pressure of the components. Mathematically you would just add up all the partial pressures to calculate the total pressure.

Part II: The Experimentally Collected Data

Boyle's Law Data

Volume of
Gas in mL

Pressure of
Gas in kPa

... 1/P ...

.. P x V ..
18.0
100

13.4
135

15.8
115

22.9
79.0

28.5
63.0

32.8
55.0

46.2
39.0

41.0
44.0

Boyle's Law Project Instructions

Part One: Graphing All graphs must either be done on graph paper or be computer generated. The graph must be labeled and all axis appropriated labeled with the correct units.

  1. Note: For consistency make the volume variable the horizontal axis for each graph.
  2. Construct a pressure volume graph. Make sure you label the axis.
  3. Calculate 1/P (inverse pressure) and and P X V and insert calculations into an appropriate chart. (Fill in the empty columns in the above data table).
  4. Graph the inverse pressure values against the volume and determine the slope of this line.
  5. Graph the product, P X V, against the volume and determine ths slope of this line.
    Hint: write the PxV values in scientific notation with only three digit accuracy. This will make for a more easily interputed graph.

Part TWO: Analysis & Questions

  1. In question 3 & 4 above a slope was determined. What is the signifigance of these slope?
  2. Explain, using Kinetic Molecular Theory, what happens to molecules of a gas as the volume of the container holding the gas is decreased. why does the pressure increase?
  3. A gas in a container witha volume of 1.45 L has a pressure of 97.5 kPa. If this container is expained to 1.86 L, what is the new pressure in this container?

Charles' Law Data

Volume of
Gas in mL

Temperature of
Gas in oC

Temperature in
Kelvin

V/T Ratio
218
100.0

195
60.0

172
20.0


160
0.0

142
-30.0

130
-50.0

Charles' Law Project Instructions

Part One: Graphing Prepare to graph your results as follows

  1. The horizonal or x-axis will be used as the temperature axis in oC (the independent variable). The range of temperature should extend from -300oC to 100 oC.
  2. The vertical or y-axis will represent the volume in mL (the dependent variable). Values should range from 0.0 to 220 mL.
  3. title your graph and label both axis.
  4. Convert each temperature measurement to Kelvin, and underneath the oC axis mark another axis in Kelvins units.
  5. Calculate the ratio of volume to temperature in K for each reading and record in an appropriately constructed chart.
  6. Calculate the slope of the line, and use it to determine the equation of the straight line you have drawn. Use the form
    y = m(x - a), and let m be the slope, and with a as the value of the x-intercept.

Part Two: Analysis & Questions

  1. Compare the ratios of temperature to volume. What do they suggest about the qualitative relationship between temperature and volume?
    1. Extrapolate your graph to the temperature axis.
    2. At what temperature would the volume become zero?
    3. In terms of Kinetic Molecular Theory, what is the signifigance of this temperature?
    4. What is a Kelvin scale?
    5. What is the theoretical value of absolute zero in degrees Celsius?
  3. If a gas with a volume of 4.58 L at 12.6oC were heated to 128.2oC, what would be the new volume of this gas, assuming that the pressure is kept constant?

Solving Gas Law Problems

Cann't solve Gaw Law problems? Maybe this will help. But the key is still problem analysis.
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Problem Help

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