Which of the following curve represents the first order reaction ?
Show Hint
- [graph (A) - image pending]
- [graph (B) - image pending]
- [graph (C) - image pending]
- [graph (D) - image pending]
The Correct Option is A
Solution and Explanation
For a first order reaction the integrated rate law is \(\ln[A] = \ln[A]_0 - kt\). This means a plot of \(\log[A]\) (or \(\ln[A]\)) against time \(t\) is a straight line with a negative slope.
Step 1:
Among the given curves, the one that shows \(\log[A]\) versus \(t\) as a straight line going downward represents first order kinetics. A simple concentration versus time curve for first order is an exponential decay, but the diagnostic linear plot is \(\log[A]\) vs \(t\).
Answer: Option (A) shows the straight line plot characteristic of a first order reaction. (Final option depends on the printed graphs, which are images.)
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[structure - image pending]
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