A process has $$\Delta $$H = 200 J mol^–1 and $$\Delta $$S = 40 JK^–1 mol^–1. Out of the values given below, choose the minimum temperature above which the process will be spontaneous :

The entropy change associated with the conversion of 1 kg of ice at 273 K to water vapours at 383 K is :

(Specific heat of water liquid and water vapour are 4.2 kJ K^$$-$$1 kg^$$-$$1 and 2.0 kJ K^$$-$$1 kg^$$-$$1; heat of liquid fusion and vapourisation of water are 334 kJ^$$-$$1 and 2491 kJ kg^$$-$$1, respectively). (log 273 = 2.436, log 373 = 2.572, log 383 = 2.583)

Consider the reversible isothermal expansion of an ideal gas in a closed system at two different temperatures T₁ and T₂ (T₁ < T₂). The correct graphical depiction of the dependence of work done (w) on the final volume (V) is :

For which of the following processes, $$\Delta $$S is negative ?