Preview - Ideal Gas Laws - Connected Chemistry 2019

It's CODAP Time!

Now let's go ahead and conduct our final computational experiment within CODAP!!!

Note: If you do not remember the exact details, you can see your initial experimental design below the CODAP window. If you are not sure about your experimental design, consult your teacher before starting. 

  1. Run each experiment long enough so that pressure stabilizes before your model reports the data.
  2. Keep non-involved parameters (e.g., number of particles, ticks-to-run) fixed at all experiments.
  3. Run at least 3 trials (repetitions) for each combination.
  4. Try at least 5 different values for the independent variable (volume/wall-position).
  5. Speed up the model to conduct the experiments as fast as possible.
     

Referenced Questions

These questions were answered in the previous steps. They are provided here for your reference.

In the next page, you will conduct your last experiment in CODAP in this unit. Design your experiment using the table below:

Dependent variable: (P)ressure
Independent variable: (V) olume
Research question:

Is there any relationship between these two variables?

If yes, what is the mathematical nature of this relationship?

Note: Once again, we cannot directly set the volume of the container. Instead, determine values for the "wall position" parameter.

Questions

Please answer the questions below.

First and foremost, save your CODAP experiment and upload it using the "Browse" button below. You can do it as follows:

  1. Click the hamburger menu () icon on he top-left corner of the CODAP window.
  2. Click Save ().
  3. Choose the Local File option ()
  4. Click Download ().
Upload files that are less than 5MB in size.
File Delete

Also, upload a screenshot of your plot.

You can export a plot in CODAP as an image:

  1. Click anywhere on the plot.
  2. From the side menu, click the camera icon.
  3. Click the "Export Image" item.
  4. A pop-up window will open. Choose the "Local File" option and then click "Download"

 

 

Upload files that are less than 5MB in size.
File Delete

At this point, if you collected enough data, you must have noticed that:

  • pressure decreases as volume increases
  • resulting plot looks more like an arc than a straight line

Both of these findings are different than our previous two explorations.

Why do you think we observe this arc-like plot? (min. 2 sentences).

Unfortunately, using the "movable line" tool would not help us in this situation because our data does not show a linear relationship. What we observe is a non-linear relationship.

The specific type of relationship we are observing can be expressed through a mathematical form as follows: y = m / x, where m is a constant coefficient.

 

On the other hand, we can use CODAP's "Plotted Function" tool to approximate a mathematical function that fits our data:

  1. Click anywhere on the plot.
  2. In the opening window, click the "Plotted Function" option.
  3. A bar with caption f() will appear on the top of the plot. 
  4. Click the function bar and write "10000 / volume" as your plotted function. This means your function is P = 10000 / V.
  5. Repeat this step until you find a coefficient value that 

What was the coefficient that fit your data the best?

What is your mathematical model (equation) that explains your data the best?

Write it as: Pressure = coefficient / Volume 

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.