JEE Advanced2018ChemistryChemical KineticsActual
Consider the following reversible reaction: A g + B g ⇌ AB g The activation energy of the backward reaction exceeds that of the forward reaction by 2 RT (in mol - 1 ). If the pre-exponential factor of the forward reaction is 4 times that of the reverse reaction, the absolute value of ∆ G ⊝ ( in J mol - 1 ) for the reaction at 300 K is ____. (Given; ln ⁡ 2 = 0 .7 , = 2500 J mol - 1 at 300 K and
Correct answer
0
Step-by-step solution
A   g + B   g ⇌ AB   g E ab - E ef = 2 RT   ⇒ ∆ H = - 2 RT   and A f A b = 4 K eq = K f K b = A f   e - E af / RT A b e - E ab / RT = 4 e 2 ∆ G o = - RTln ⁡ K = - 2500 × ln ⁡ 4 × e 2 = - 8500 J / mol ∴     Absolute value of ∆ G o - 8500   J / mol