1) One mole of an ideal gas at 300 k is expanded isothermally from an initial volume of 1 litre to 10 litres. Then $\triangle$ S (cal deg-1 mol-1) for this process is : (R=2 cal K-1 mol-1) A) 7.12 B) 8.314 C) 4.6 D) 3.95 Answer: Option CExplanation:For an isothermal process $\triangle S= 2.303 nR \log\frac{V_{2}}{V_{1}}$ $\triangle S= 2.303 \times1\times2\times\log \frac{10}{1}$ = 4.6 cal deg-1 mol-1