The half-life period of a first order chemical reaction is 6.93 minutes. The time required for the completion of 99% of the chemical reaction will be (log 2 = 0.301):

1. 23.03 minutes

2. 46.06 minutes

3. 460.6 minutes

4. 230.3 minutes

Subtopic:  First Order Reaction Kinetics |
 77%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

A drop of solution (volume 0.05 mL) contains 3.0 x10-6 mole of H+. If the rate constant of disappearance of H+ is 1.0x107 mol litre sec?. How long would it take for H+ in drop to disappear?

1. 6x10-8 sec

2. 6x10-7 sec

3. 6x10-9 sec

4. 6x10-10 sec

Subtopic:  Order, Molecularity and Mechanism |
 56%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

A zero order reaction is one:

1. in which reactants do not react

2. in which one of the reactants is in large excess

3. whose rate does not change with time

4. whose rate increases with time

Subtopic:  Order, Molecularity and Mechanism |
 71%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

For A + B → C + D, H = -20 kJ mol-1 , the activation energy of the forward reaction is 85 kJ mol-1. The activation energy for the backward reaction is…. kJ mol-1.

1. 105 2. 85
3. 40 4. 65
Subtopic:  Arrhenius Equation |
 77%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Given that K is the rate constant for some order of any reaction at temperature T. Then the value of \(\lim\limits_{T \to \infty} log~k\) = (where A is the Arrhenius constant):
1. \(\frac{\text A}{2.303}\)
2. \(\text A\)
3. \(2.303~\text A\)
4. \(log~\text A\)
Subtopic:  Arrhenius Equation |
 50%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

For the elementary reaction M  N, the rate of disappearance of M increases by a factor of 8 upon doubling the concentration of M. The order of the reaction with respect to M will be:

1. 4

2. 3

3. 2

4. 1

Subtopic:  First Order Reaction Kinetics |
 76%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

The rate constant value for a zero-order reaction is 2 x10-2 mol L-1 sec-1. If the concentration of the reactant after 25 sec is 0.5 M, then the initial concentration of reactant is: 

1. 0.5 M

2. 1.25 M

3. 12.5M

4. 1.0 M

Subtopic:  Order, Molecularity and Mechanism |
 74%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The rate constant for a second order reaction is 8x10-5 M-1 min-1 . How long will it take a 1M solution to be reduced to 0.5M?

1. 8.665 x 103 minute

2. 8 x 10-5 minute

3. 1.25 x 104 minute

4. 4x10-5 minute

Subtopic:  Order, Molecularity and Mechanism |
 69%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

The activation energy for a reaction is 9.0 kcal/mol. The increase in the rate constant when its temperature is increased from 298K to 308K is:

1. 10%

2. 100%

3. 50%

4. 63%

Subtopic:  Arrhenius Equation |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

For a certain reaction of order \('n'\) the time for half change \(t_{1/2}\) is given by; \(=,t_{1/2}=\dfrac{2-\sqrt2}{K}\times C^{1/2}_0,\) where \(K\) is rate constant and \(C_0\) is initial concentration. The value of \(n\) is:

1. 1

2. 2

3. 0

4. 0.5

Subtopic:  First Order Reaction Kinetics |
 65%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints