An isolated box is divided into two equal compartments by a partition (see figure). One compartment contains a van der Waals gas while the other compartment is empty. The partition between the two compartments is now removed. After the gas has filled the entire box and equilibrium has been achieved, which of the following statement(s) is (are) correct?
An isolated box is divided into two equal compartments by a partition (see figure). One compartment contains a van der Waals gas while the other compartment is empty. The partition between the two compartments is now removed. After the gas has filled the entire box and equilibrium has been achieved, which of the following statement(s) is (are) correct?
Show Hint
- Internal energy of the gas has not changed.
- Internal energy of the gas has decreased.
- Temperature of the gas has increased.
- Temperature of the gas has decreased.
The Correct Option is B
Solution and Explanation
When the partition is removed, the gas expands to fill the entire volume. This expansion is an irreversible process, and in most cases, it will result in a decrease in the internal energy of the gas, assuming no heat exchange with the surroundings. This is because the gas has to do work to expand into the empty compartment.
Step 2: Conclusion.
Thus, the correct answer is option (B).
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