A2L Item 115

Goal: Reasoning about temperature.

Source: UMPERG-ctqpe186

Two moles of an ideal gas fill a volume of 10 liters with a pressure of
2.4 atm. The gas is thermally insulated from the surroundings. A
membrane is broken which allows the gas to expand into the new volume
which is 3 times as large as the old volume. The new temperature is …

  1. The same as before.
  2. Lower than before.
  3. Higher than before.
  4. Cannot be determined.



(1) Students may erroneously apply prior knowledge that gas cools as it
expands. Some will likely think that the answer cannot be determined
without more information.