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 :

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 :