Pressure can be defined as the frequency and force with which gas particles collide with the walls of their container.

Since we are examining pressure and number of particles in this simulation, we need to make sure that the other two variables (volume and temperature) are held constant. 

This is the set-up you will need to complete the data table below: 

1. Click "Ideal".
2. Under "Hold Constant", click "Volume (V)". The program does not allow you to hold two things constant at the same time, but as long as you do not manipulate the "hot-cold" switch the temperature will remain at 300 K.
3. Click the green plus sign next to particles.
4. Click the double rightward facing triangle below "Heavy" to add 50 heavy particles at once.
5. Wait until all particles from the pump have had a chance to hit a wall of the container, then record the highest pressure observed.
6. Press the reset button, then repeat steps #2-5 two more times.
7. Complete steps #2-6 for 100 heavy particles and 150 heavy particles.