For zero order reaction
$\begin{aligned}
& \text { Half life }=\frac{A_o}{2 k} \
& 60 \min =\frac{2}{2 k} \
& k=\frac{1}{60} \mathrm{M} / \min
\end{aligned}$
Now
At=Ao−ktt=kAo−At=1/600.5−0.250.25×60
t=15 min
JEE Main 2025 — Chemistry Physical Chemistry
Half life of zero order reaction A→ product is 1 hour, when initial concentration of reaction is 2.0 mol L L−1. The time required to decrease concentration of A from 0.50 to 0.25 mol L−1 is:
Held on 4 Apr 2025 · Verified 6 Jul 2026.
0.5 hour
4 hour
15 min
60 min
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