# Simulation

Simulation
Behavior of Gases: Finding the Molar Mass of a Fictitious
Gas Using Temperature and Average Velocity
OBJECTIVES
• Determine the molar mass of a fictitious gas in a simulation
• Learn the relationship between temperature and kinetic energy
INTRODUCTION
The molecules of matter at ordinary temperatures can be considered to be in ceaseless,
random motion at high speeds. The average translational kinetic energy for these molecules
can be deduced from the Boltzmann distribution. Knowing the velocity and the temperature of
these molecules at different temperatures will allow us to calculate a value for the Molar Mass.
The Boltzmann distribution of energies can be broken down to relate average velocities to
temperature using the following relation:
k = 1.38 x 10-23 J/K
T in Kelvin
m of a single particle in kg
v in m/s
We can eliminate the 1/2 factor by multiplying both sides by 2 giving us:
Gas Pressure and Temperature Relationships –
Simulation
A. QUALITATIVE DATA
1. What do you expect to happen to the pressure of a gas when a sealed system heats up?
B. SETTING UP THE EXPERIMENT
1. Click on “Constant Volume”
2. Click on “Measurement Tools”, then select “Species Information”
3. Click on “Advanced Options” and deselect “Molecules Collide”
4. Chose the “Light Species”
5. Record your data from the experiment in the table below for Temperature, Pressure, and
number of particles.
6. Reset the experiment if needed.
Light Species T(K) Pressure (atm) Number of Particles
Light Species T(K) Pressure (atm) Number of Particles
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