An ideal gas occupies an unknown volume V liters (L) at a pressure of 12 atm . The gas is expanded isothermally against a constant external pressure of 2 atm so that its final volume become 3 L . The work involved for this expansion process is ____ cal(Round off to two decimal places) (Gas constant $\mathrm{R}=0.082 \mathrm{L} \mathrm{atm} \mathrm{mol}^{-1} \mathrm{K}^{-1}=2 \mathrm{cal} \mathrm{mol}^{-1} \mathrm{K}^{-1}$ )
Answer
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