First Order Reaction Kinetics
High-Yield Trend
Questions 9 MCQs
The reaction of hydrogen and iodine monochloride is given as:
H2(g) + 2ICl(g) → 2HCl(g) + I2(g)
This reaction is of first order with respect to H2(g) and ICl(g), for which of the following proposed mechanisms:
Mechanism A:
H2(g) + 2ICl(g) → 2HCl(g) + I2(g)
Mechanism B:
H2(g) + ICl(g) →HCl(g) + HI(g); slow
HI(g) + ICl(g) →HCl(g) + I2(g); fast
1. B Only
2. A and B both
3. Neither A nor B
4. A only
In a first order reaction A B, if k is rate constant and initial concentration of the reactant A is 0.5 M then the half-life is :
(1)
(2)
(3)
(4)
If 60% of a first-order reaction was completed in 60 min, 50% of the same reaction would be completed in approximately:
(log 4 = 0.60, log 5 = 0.69)
| 1. | 50 min | 2. | 45 min |
| 3. | 60 min | 4. | 40 min |
Which of the following represents the factor by which the rate of a zero-order reaction increases when the temperature is raised from 10°C to 100°C, if the rate doubles for every 10°C rise in temperature?
1. 256 times
2. 512 times
3. 64 times
4. 128 times
A first-order reaction has a specific reaction rate of
10–2 sec–1. How much time will it take for 20 g of the reactant to reduce to 5 g?
| 1. | 138.6 sec | 2. | 346.5 sec |
| 3. | 693.0 sec | 4. | 238.6 sec |
If the rate constant for a first order reaction is k, the time (t) required for the completion of 99% of the reaction is given by:
1. t = 2.303/k
2. t = 0.693/k
3. t = 6.909/k
4. t = 4.606/k
For a first-order reaction A Products, initial concentration of A is 0.1 M, which becomes 0.001 M after 5 minutes. Rate constant for the reaction in min-1 is
| 1. | 0.2303 | 2. | 1.3818 |
| 3. | 0.9212 | 4. | 0.4606 |
(Given: log 2=0.301)
| 1. | 210 s | 2. | 21.0 s |
| 3. | 69.3 s | 4. | 23.1 s |
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Preparing First Order Reaction Kinetics for NEET
First Order Reaction Kinetics is a specific sub-topic that frequently appears in the NEET examination. Understanding the underlying principles and practicing targeted questions is key to mastering this concept.
The questions compiled above are previous year questions (PYQs) directly related to First Order Reaction Kinetics. Practicing these specific questions helps you understand the difficulty level and the examiner's approach to this topic.
Topic Frequently Asked Questions
Is First Order Reaction Kinetics a high-weightage topic?
You can refer to the priority and consistency badges at the top of this page. High priority topics should be thoroughly revised multiple times before the exam.
Should I memorize the solutions?
No, it is highly recommended to understand the core concept and methodology behind each solution rather than memorizing them, as exact questions are rarely repeated, but the concepts definitely are.