Preview - Ideal Gas Laws - Connected Chemistry 2019

Drawing conclusions from data: finding a quantitative relationship

So far, we collected many data points from the Bike Tire model, we plotted them, and saw a consistent relationship. We stated our findings verbally such as "the more particles in the box, the higher is the pressure".

However, verbal statements cannot help us answer questions such as: "What happens if I add 10 more particles to the box?" or "Approximately how many particles are inside the box if the pressure is 440?"

To answer such quantitative questions, we need to develop mathematical equations.

CODAP makes it trivially easy to develop such mathematical equations from data :

  1. Load your CODAP savefile by clicking CODAP's hamburger menu () and then clicking "Open".
  2. Open your file from the "Local File" section. You should have all your data back in the "Experiment Results" table, as well as your plot.
  3. Click anywhere on the plot, and then click the ruler icon ().
  4. Click the  option.
  5. A line with three anchor points will appear. Move the line as shown on the right to fit the data as best as you can.
  6. Note the linear equation 🔗 (with yellow background) that CODAP generates for us.

 

Questions

Please answer the questions below.

A linear equation, like the one you developed in CODAP, takes the form y = mx + b where:

  • y is your dependent variable (Pressure)
  • x is your independent variable (Number of Particles)
  • m (or the slope of the moveable line) represents the rate of change (e.g., pressure per particle).
  • and b is where your line intercepts the y-axis. To make things even simpler, we can ignore this number for now.

 

What is the linear equation you developed in CODAP from data? Use P instead of y and N instead of x. Write it in the following form: P = m x N  (for example, P = 1.5 x N).

Also export an image of your CODAP plot. Please download your plot and upload it using the "Browse" button below

Here's how you can do it:

  1. Click anywhere on the "Experiment Results" table, a sidebar will pop-up on the right.
  2. Click the last icon ().
  3. Choose the  "Local Data" option on the left and click "Download".
Upload files that are less than 5MB in size.
File Delete

Save the latest version of your CODAP file and upload it again.

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

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.