What can I expect to get out of doing this part of the activity?

Users can design their own activities, presentations, and demonstrations.

In this activity you will explore the capacity of LOGAL Chemical Kinetics to support:

Enter Explorations from the main menu and select Rates of Diffusion. Start the activity by clicking on the green arrow. Follow the directions provided. Remember you can opt to view text and no sound by clicking on the yellow text button. Continue recording your predictions on the screen. Notice that you are even able to draw on a graph. After you have finished review your statements by using the Answer Checker.

Click on Temperature & Diffusion. Pull down the Windows Menu at the top of the screen. Highlight Work Window Tools (image at right). Click on the Bar Chart Tool.

• Click and drag on any empty space in the Work Window to create a bar chart display.
• A definition box will immediately open. Select the Ouput Menu and scroll down to A-B Collisions.
• Slide across and select Total #. Before closing the definition box, change the Min to 0. Also type a label (e.g., Total Collisions) in the appropriate box.
• Click on the Hand Tool to return from the design mode of the simulation.
• Run the simulation. Don't forget to remove the wall.
• Now alter as many different parameters and observe any changes in total number of collisions.

Why couldn't we chart effective number of collisions?

• Click on Effects: Mass & Diffusion.
• On the Work Window Tools (image at right), click on the Numeric Display Tool.
• Click and drag to place a numeric display on any empty space in the Work Window. A definition box will immediately open. Select the Ouput Menu and scroll down to A-B Collisions. Slide across and select Total #.
• Make sure to return to the Hand Tool before running the simulation.

Numeric Display Definition Box

Now it is your turn to design your own independent investigation. If the masses of molecules A and B were the same, would different sizes change the rate of diffusion? Why or why not? Change the model window parameters to test your answer. Record your total number of collisions on the spreadsheet. Graph your results.

Make sure that you explore all conditions that could change the rate of diffusion. Try other options found on the Work Window Tools.

Further Reflection
__ Visit the LCK Discussion area again to read more of the dialogue and share your insights and questions.