You must have a JavaScript 1.1 savvy browser, like Netscape 3.0, to use this page.You should disable the 'submitting an insecure form' warning in your browsers preferences or option menu. If you don't the results window will be sent to the back when you check your results. (You can retrieve it by using the window button in the menu bar).
Press the Start button to get your numerical assignment!
You can only submit this page once. Press Reset to clear your answers and Start for another attempt. Do not attempt to change the problem data.
Constants
and
Conversions
. Need a
calculator
? How about some
hints
.
Make sure to enter your answers in the specified units, but do not include the units in your answer.
First Name:
Last Name:
Fig 1
1) In the process of taking a gas trom state a to state c along the curved path shown in Fig. 1,
J of heat leave the system and 40 J of work are done on the system. What is the change in internal energy to the nearest Joule? .
2) When the gas is taken along the path cda, the work done by the gas is W = 38 J. How much heat Q is added to the gas in the process cda?
3) If P
a
=
P
d
, how much work (to the nearest tenth of a Joule) is done by the gas in the process abc?
4) In problem 3), if U
a
-U
c
=20J, what is Q (to the nearest Joule) for path abc?
Fig 2
5) Consider the following two-step process. Heat is allowed to flow out of an ideal gas at constant volume so that its pressure drops from 5 atm to
atm. Then the gas expands at constant pressure, from an initial volume of 200 L to a final volume at which the temperature reaches it's original value. See Fig. 2. Calculate the total heat flow, to the nearest Joule, into or out of the gas.
6) An ideal gas expands at a constant pressure of
atm from 300 L to 900 L. Heat then flows out of the gas, at constant volume, and the pressure and temperature are allowed to drop until the temperature reaches half of its original value. What is the total work (to the nearest Joules) done by the gas in the process?
7) In problem 6) what is the total heat (to the nearest Joules) flow into the gas?
8) One kilogram of water is taken from
degrees C to degrees 80 C. Estimate the change in entropy (to the nearest J/K) of the water.
9) What is the change in entropy (to the nearest J/K) of
grams of water at 0 degrees C when it is frozen into ice at 0 degrees C?
10) If the water in problem 9) were frozen by being placed in contact with a temperature reservoir at -30 degrees C, what would be the total entropy change (to the nearest J/K) of the reservoir and water taken together?