Since half life is independent of intial concentration of the reactant, it's a first order reaction
k=t21ln2
kt=2.303logAA0
t21ln2t=2.303logAA0
2002.303log2t=2.303log20100
t=0.3200×log5=466.67sec≈467sec
JEE Main 2022 — Chemistry Physical Chemistry
At 30∘C, the half life for the decomposition of AB2 is 200s and is independent of the initial concentration of AB2. The time required for 80 of the AB2 to decompose is (Given: log2=0.30; log3=0.48)
Held on 26 Jul 2022 · Verified 6 Jul 2026.
200s
323s
467s
532s
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