ΔG∘=−RT ln KC
2494.2=−8.314×300 ln KC
2494.2=−8.314×300×2.303 log KC
−2.303×300×8.3142494.2=−0.44=log KC
log KC=−0.44
KC=0.36
Q=[A]2[B][C]=(21)22×21=4
Q>KC, reaction will shift in reverse direction.
The standard Gibbs energy change at 300 K for the reaction 2A⇌ B+C is 2494.2 J. At a given time, the composition of the reaction mixture is [A]= 1 2,…
JEE Main 2015 — Chemistry Physical Chemistry
2015mcqmedium
The standard Gibbs energy change at 300 K for the reaction 2A⇌B+C is 2494.2 J. At a given time, the composition of the reaction mixture is [A]=21,[B]=2 and [C]=21 . The reaction proceeds in the: [R=8.314J/K−mol,e=2.718] {Given antilog (-0.44)=0.36}
Official previous-year question
Held on 4 Apr 2015 · Verified 6 Jul 2026.
Options
- A
Reverse direction because Q<KC
- B
Forward direction because Q>KC
- C
Reverse direction because Q>KC
- D
Forward direction because Q<KC
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