For one mole of an ideal gas, which of these statements must be true?
(a) U and H each depends only on temperature
(b) Compressibility factor z is not equal to 1
(c) C_{P, m} – C_{V, m} = R
(d) dU = C_VdT for any process

The true statement amongst the following is :

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

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 :