Question
For a certain reaction R $\rightarrow$ Product, the plot of [R] vs time has a negative slope as shown. The order of reaction is :
This question was previously asked in
NEET UG Re-Exam 2026 Question Paper (21-Jun-2026)
The correct answer is
0
To determine the order of the reaction, we need to analyze the given plot of [R] (concentration of reactant) versus time.
The plot shows a linear decrease in the concentration of R with time, indicating a constant rate of reaction regardless of the concentration of R.
Step-by-step Explanation:
- A zero-order reaction is characterized by a constant reaction rate, which is independent of the concentration of reactants.
- The rate of reaction for a zero-order reaction is given by the formula: \(v = -\frac{{d[R]}}{{dt}} = k\) where \(k\) is the rate constant.
- In a zero-order reaction, the concentration of reactant decreases linearly with time, which results in a straight line with a negative slope in the plot of [R] vs. time.
- Thus, the linear plot with a negative slope confirms that the reaction is zero-order.
Conclusion: The order of the reaction is 0 (zero-order reaction).
This option is justified as the plot supports the characteristic behavior of a zero-order reaction where the concentration of the reactant decreases linearly with time.
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