rate of reaction =2×10−5 mol L−1 s−1⇒ order of reaction is n=1 rate =K[A]n[ A]=0.01M⇒K=0.012×10−5=2×10−3 K=t1/20.693t1/2=2×10−30.693=346.5 s Related Theory For a first-order reaction, a graph plotted with ln[A] on the Y-axis and time on the X-axis, will be a straight line with a slope of −k. 
For a first order reaction A → B the reaction rate at reactant concentration of 0.01 M is found to be 2.0 × 10^-5 ~mol ~L^-1 s^-1. The half life…
NEET UG 2005 — Chemistry Physical Chemistry
2005mcqmedium
For a first order reaction A→B the reaction rate at reactant concentration of 0.01M is found to be 2.0×10−5 mol L−1 s−1. The half life period of the reaction is:
Official previous-year question
Held on 30 Apr 2005 · Verified 9 Jul 2026.
Options
- A
30 s
- B
220 s
- C
300 s
- D
347 s
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