COMEDK · Chemistry · 19. Chemical Kinetics
Choose the correct statement.
- A Molecularity of a chemical reaction is always greater than order of the reaction.
- B The plot of [A] versus time "t" for a zero order reaction is a horizontal line parallel to the x -axis which represents " t "
- C For a first order reaction the time taken for \(3 / 4^{\text {th }}\) completion is 2 times the half-life period.
- D For a second order reaction the rate of reaction with respect to reactant becomes 27 times when its concentration is tripled.
Answer & Solution
Correct Answer
(C) For a first order reaction the time taken for \(3 / 4^{\text {th }}\) completion is 2 times the half-life period.
Step-by-step Solution
Detailed explanation
Molecularity is the number of reacting species taking part in an elementary reaction and is always a positive integer, whereas order of reaction can be fractional or zero. Thus, molecularity is not always greater than the order of reaction. For a zero order reaction, the rate…
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