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One mole of an ideal monoatomic gas is compressed isothermally in a rigid vessel to double its pressure at room temperature, 27°C. The work done on the gas will be:

1. 300R ln 6
2. 300R
3. 300R ln 7
4. 300R ln 2

Correct answer: 300R ln 2

Solution

For isothermal compression of 1 mole at T=300 K with pressure doubled, volume halves, so work done on the gas = nRT ln(P2/P1) = 300R ln2.

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