For a dimerization reaction,
2A(g) $$ \to $$ A₂(g)
at 298 K, $$\Delta $$U^o = –20 kJ mol^–1, $$\Delta $$S^o = –30 JK^–1 mol^–1,
then the $$\Delta $$G^o will be _____ J.

The heat of combustion of ethanol into carbon dioxide and water is – 327 kcal at constant pressure. The heat evolved (in cal) at constant volume and 27^oC (if all gases behave ideally) is (R = 2 cal mol^–1 K^–1) ________.

The internal energy change (in J) When 90 g of water undergoes complete evaporation at 100^oC is ____________.

(Given : $$\Delta $$H_vap for water at 373 K = 41 kJ/mol,
R = 8.314 JK^–1 mol^–1)

At constant volume, 4 mol of an ideal gas when heated from 300 K to 500K changes its internal energy by 5000 J. The molar heat capacity at constant volume is _______.