Consider 5.5 L of a gas at a pressure of 3.0 atm in a cylinder with a movable piston. The external pressure is changed so that the volume changes to 10.5 L.
a. Calculate the work done, and indicate the correct sign.
b. Use the preceding data but consider the process to occur in two steps. At the end of the first step, the volume is 7.0 L. The second step results in a final volume of 10.5 L. Calculate the work done, and indicate the correct sign.
c. Calculate the work done if after the first step the volume is 8.0 L and the second step leads to a volume of 10.5 L. Does the work differ from that in part b? Explain.
7. In Question 6 the work calculated for the different conditions in the various pans of the question was different even though the system had the same initial and final conditions. Based on this information, is work a state function?
a. Explain how you know that work is not a state function.
b. Why does the work increase with an increase in the number of steps?
c. Which two-step process resulted in more work, when the first step had the bigger change in volume or when the second step had the bigger change in volume? Explain.
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Chemistry: An Atoms First Approach
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