At 2 7 ∘ C and 1 bar gaseous N 2 O 4 is 50% dissociated upto equilibrium. N 2 O 4 ⇌ 2 NO 2 Calculate magnitude of molar standard Gibbs free energy change (in cal) 2 7 ∘ C . [Given : ln 2 = 0

Question

At 2 7 ∘ C and 1 bar gaseous N 2 ​ O 4 ​ is 50% dissociated upto equilibrium. N 2 ​ O 4 ​ ⇌ 2 NO 2 ​ Calculate magnitude of molar standard Gibbs free energy change (in cal) 2 7 ∘ C . [Given : ln 2 = 0.7 , ln 3 = 1.1 ]

TestHub · Accepted Answer

N 2 ​ O 4 ​ ⇌ 2 NO 2 ​ Initial moles 1 0 At eqm mole 1 − α 2 α K P ​ = ( 1 − α 2 ) ( 2 α ) 2 P ​ = 1 − ( 0.5 ) 2 4 ( 0.5 ) 2 × 1 ​ = 3 4 ​ Δ G ∘ = − RT ln K P ​ = − 2 × 300 ln ( 3 4 ​ ) = − 2 × 300 × 0.3 = − 180 cal. ∣ Δ G ∘ ∣ = 180 .

Chemistry - Thermodynamics - II Question with Solution | TestHub

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