For an ideal gas undergoing a reversible isothermal expansion, the Gibbs energy and Helmholtz energy functions are defined as G = H − TS and A = U − TS respectively. Which of the following statements are correct? (A) ΔG = ΔA (B) Δ(pV) = 0 (C) ΔG > ΔA (D) Δ(nRT) = 0

Consider the following reaction: 2A (g) + B (g) → 2D (g) ΔU⊖ = -10 kJ mol-1 and ΔS⊖ = -44 J K-1 at 298 K. Identify the correct option with ΔG⊖ for the reaction and spontaneity of the reaction at 298 K. (Given: R = 8.314 J mol-1 K-1)

At a certain temperature, T (K), during a process, 500 J is absorbed by the system and work of 200 J is done by the system. Then change in internal energy of the system is: