If the standard molar enthalpy change for combustion of graphite powder is $$-$$2.48 $$\times$$ 10² kJ mol^$$-$$1, the amount of heat generated on combustion of 1 g of graphite powder is ___________ kJ. (Nearest integer)

For a given chemical reaction A $$\to$$ B at 300 K the free energy change is $$-$$49.4 kJ mol^$$-$$1 and the enthalpy of reaction is 51.4 kJ mol^$$-$$1. The entropy change of the reaction is _____________ JK^$$-$$1 mol^$$-$$1.

For the reaction C₂H₆ $$ \to $$ C₂H₄ + H₂

the reaction enthalpy $$\Delta$$_rH = __________ kJ mol^$$-$$1. (Round off to the Nearest Integer).

[ Given : Bond enthalpies in kJ mol^$$-$$1 : C-C : 347, C = C : 611; C-H : 414, H-H : 436 ]

The standard enthalpies of formation of Al₂O₃ and CaO are $$-$$1675 kJ mol^-1 and $$-$$635 kJ mol^$$-$$1 respectively.

For the reaction

3CaO + 2Al $$ \to $$ 3Ca + Al₂O₃ the standard reaction enthalpy $$\Delta$$_rH⁰ = _________ kJ.

(Round off to the Nearest Integer)