If enthalpy of atomisation for Br₂₍₁₎ is x kJ/mol and bond enthalpy for Br₂ is y kJ/mol, the relation between them :

An ideal gas is allowed to expand form 1 L to 10 L against a constant external pressure of I bar. The work done in kJ is :

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 :