Second Virial Coefficient

Ethane and Carbon Dioxide are the best gases for this simulated experiment.

1. Select temperature = 0 and a gas.

2. Move the piston to its highest position.  Click on Record.

3. Lower the piston in small increments (perhaps 0.2 ml), recording data for volumes down to the smallest value (0.4 ml).

4. Change the temperature to 250 oCRecord data as in 2-3 above.

5. Change the temperature to 500 oCRecord data as in 2-3 above.

6. Click on select graph type .

7. Select PV vs P (constant T) .  Click on graph It .

8. Observe that the slopes of the lines change slightly with temperature.

9. Record the information about the lines you have generated.

10. Calculate the virial coefficient:
      (B' = slope / intercept) at each temperature.

11. Estimate the Boyle temperature (B' = 0) for this gas.

12. Calculate the second virial coefficient at each temperature:
        B = RTB' .

13. Calculate the number of moles of gas from each set of data:
        n = RT x slope .

    Discuss your observations.