Preview - Ideal Gas Laws - Connected Chemistry 2019

Our experimental setup: the "warm up -- cool down" model

Let us begin our exploration of the relationship between gas pressure and gas temperature with another NetLogo model. In this model, we have a fixed-volume gas container similar to our previous Bike Tire model. However, this model allows us to warm up and cool down the walls of the container. 

When a particle hits the wall, two things may happen:

  • If it has more kinetic energy than the energy of the wall, it will loose some of its energy.
    • the loss of energy is dependent on the difference between the particle's energy and the wall's energy.
  • If it has less energy than the energy of the wall, it will gain some energy.
    • the gain of energy is dependent on the difference between the particle's energy and the wall's energy.
  • Particles only have kinetic energy. The higher a particle's kinetic energy, the faster it moves.
    • a particle will speed up if it gains energy from the wall
    • a particle will slow down if it looses energy to the wall

 

Now begin exploring the model:

  1. Run the model by clicking "setup" and then clicking "go".
  2. Wait until all three plots stabilize.
  3. Warm up the walls (at least 6).
  4. Observe the changes in plots.
  5. Repeat the same steps, but this time cool down the walls.

Some quick notes: The temperature of a gas is related to the average speed of the particles. When the average particle speed increases, the temperature also increases. However, this is not a linear relationship. Gas temperature is proportional to the square of the average particle speed. For example, if you double the average speed, you will quadruple the temperature.

Even though temperature and average particle speed are not directly proportional, when one increases the other will too. This means we can still use them to make comparisons and develop mathematical models.

Questions

Please answer the questions below.

What happens to the particles when you warm up the walls of the container? Briefly describe the events you observe. (min. 2 sentences)

Quick tip: You can use the  slider.

What happens to the particles when you cool down the walls of the container? Briefly describe the events you observe. (min. 2 sentences)

Quick tip: You can use the  slider.

What changes did you observe in the plots? Briefly describe how each plot changes when you warm up the walls. (min. 3 sentences)

In the next page, you are going to conduct another computational experiment. Once again, you will conduct an experiment to answer a pre-determined research question:

Dependent variable: (P)ressure
Independent variable: (T)emperature
Research question:

Is there any mathematical relationship between these two variables?

If yes, what is the nature of this relationship?

Note: Remember that you cannot manipulate the gas temperature directly. You can manipulate it only indirectly by manipulating the "outside energy" parameter. Hence, the table below does not have a "temperature" column. 

 

Also note: Remember the experiment you ran in the previous lesson and also remember that you will run this experiment within CODAP in the next page.

Notes

These notes will appear on every page in this lesson so feel free to put anything here you'd like to keep track of.