Match List-I with List-II.
| List-I | List-II |
| A. Order of complex reaction is determined by | I. Instantaneous rate |
| B. Rate of zero order reaction is equal to | II. Rate law |
| C. Relationship between rate of reaction and concentrations of reactants | III. Order of slowest step |
| D. Rate at particular moment of time | IV. Rate constant |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → A-III, B-IV, C-II, D-I
A. Order of complex reaction is determined by — This matches III. Order of slowest step. A complex reaction takes place in several steps, and the slowest step decides the rate of the whole reaction.
B. Rate of zero order reaction is equal to — This matches IV. Rate constant.
\( \displaystyle \text{Rate} = k[R]^0 = k \)
C. Relationship between rate of reaction and concentrations of reactants — This matches II. Rate law. The rate law (rate equation) expresses the rate in terms of the concentrations of the reactants, e.g. Rate = k[A]x[B]y.
D. Rate at particular moment of time — This matches I. Instantaneous rate. It is the slope of the tangent to the concentration–time curve at that moment, −d[R]/dt.
Shortcut: The pair B-IV appears in Options (2) and (3), and C-II then leaves only Option (2).