A(g)⟶2 B( g)+C(g)
t=0t→∞P002P0P0
P∞=3P0P0=240=80 mm of Hg
Kt=ln(P∞−PtP∞−P0)
K×10=ln(240−160240−80)
K=10ℓn2=0.0693 min−1
Option (3) is incorrect
JEE Main 2025 — Chemistry Physical Chemistry
2025mcqeasy
Reaction A(g)→2 B( g)+C(g) is a first order reaction. It was started with pure A
Which of the following option is incorrect?
Official previous-year question
Held on 7 Apr 2025 · Verified 6 Jul 2026.
Options
- A
Initial pressure of A is 80 mm Hg
- B
The reaction never goes to completion
- C
Rate constant of the reaction is 1.693 min−1
- D
Partial pressure of A after 10 minute is 40 mm Hg
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