Enthalpy of sublimation of iodine is 24 cal g^–1 at 200 ^oC. If specific heat of I₂(s) and l₂ (vap) are 0.055 and 0.031 cal g^–1K ^–1 respectively, then enthalpy of sublimation of iodine at 250 ^oC in cal g^–1 is :

The difference between $$\Delta $$H and $$\Delta $$U ($$\Delta $$H – $$\Delta $$U), when the combustion of one mole of heptane(l) is carried out at a temperature T, is equal to :

A process will be spontaneous at all temperatures if :

During compression of a spring the work done is 10kJ and 2kJ escaped to the surroundings as heat. The change in internal energy, $$\Delta $$U(inkJ) is :