### SimuLab 6: Charles' Law - Movie

 Your objective is to: Recognize the microscopic origin of the volume variations with temperature at constant external pressure. You will be able to: State Charles' Law. Construct a volume versus temperature graph from collected data. State the relationship between volume and temperature. Determine the temperature at which the volume would be zero and explain the significance of this point. Propose reasons as to why the  V/T value deviates from predictions of Charles' Law. State the relationship between number density and temperature.

 1. Open SMDPlayer, select Charles in the IdealGas folder. Select Show Averages. Press Play to resume the movie. The movie pauses at each explanatory caption. Follow the instructions in each caption, making sure to Reset Averages in the Average Values panel. Repeat this step until the end of the movie is reached. If you wish to see the temperature in Kelvin scale press Real Units button.
 Notice that the average pressure stays approximately the same throughout the entire movie. Note that the temperature throughout the movie decreased by a factor of 2.5. In our simulation, the temperature of the gas sample is equal to the average kinetic energy of the molecules. The average kinetic energy is proportional to the average velocity squared (Ek=( (mv2)/2) avg). Therefore, the average velocity is decreased by Ö{2.5} » 1.6. Did you notice that the particles move slower at the end of the movie than at the beginning? To compare, you can watch the movie again.

 T1 T2 T3 T4 T5 Temperature Pressure NumberDensity (N/V) Volume V/T Deviation from average % Deviation

Calculate average (  V/T) avg value =  åi5 (Vi)/(Ti)   :  ______________

Deviation from average = |( V/T)i -( V/T)ave|

% Deviation = (|( V/T)i -( V/T)ave|)/(( V/T)avg) ×100

 Q2.35: Plot Volume vs. Temperature on a graph. Draw a line of best fit through the points.

 Q2.36: What is the relationship between volume and temperature?

 Q2.37: On a Volume vs. Temperature graph, for an ideal gas the line intersects the temperature axis at the origin. Comment on the extent to which your graph is consistent with Charles' Law.

 Q2.38: Compare the values of  V/T for various temperatures. Find the average value of these ratios and calculate the deviation of each  V/T value from the average. Calculate the percent deviation of each ( V/T) i value: and calculate the average percent deviation.

 Q2.39: Plot the Number density vs. Temperature graph.

 Q2.40: How does number density vary with temperature?