← Back to Chemistry

Chemical Kinetics

72 Questions Start NEET Test
All Exams NEET AIIMS
2009 Q51 NEET MCQ
10 Mar 2026
In the reaction,
BrO$_{3(aq)}^ - $ + 5Br$_{(aq)}^ - $ + 6H+ $ \to $ 3Br2(l) + 3H2O(l).
The rate of appearance of bromine (Br2) is related to rate of disappearance of bromide ions as
A.
${{d\left[ {B{r_2}} \right]} \over {dt}} = - {5 \over 3}{{d\left[ {B{r^ - }} \right]} \over {dt}}$
B.
${{d\left[ {B{r_2}} \right]} \over {dt}} = {5 \over 3}{{d\left[ {B{r^ - }} \right]} \over {dt}}$
C.
${{d\left[ {B{r_2}} \right]} \over {dt}} = {3 \over 5}{{d\left[ {B{r^ - }} \right]} \over {dt}}$
D.
${{d\left[ {B{r_2}} \right]} \over {dt}} = - {3 \over 5}{{d\left[ {B{r^ - }} \right]} \over {dt}}$
2009 Q52 NEET MCQ
10 Mar 2026
For the reaction A + B $ \to $ products, it is observed that

(i)  on doubling the initial concentration of A only, the rate of reaction is also doubled and
(ii)  on doubling the initial concentration of both A and B, there is a change by a factor of 8 in the rate of the reaction.

The rate of this reaction is given by
A.
rate = k[A]2 [B]2
B.
rate = k[A] [B]2
C.
rate = k[A] [B]
D.
rate = k[A]2 [B]
2009 Q53 NEET MCQ
10 Mar 2026
Half-life period of a first order reaction is 1386 seconds. The specific rate constant of the reaction is
A.
0.5 $ \times $ 10$-$2 s$-$1
B.
0.5 $ \times $ 10$-$3 s$-$1
C.
5.0 $ \times $ 10$-$2 s$-$1
D.
5.0 $ \times $ 10$-$3 s$-$1.
2008 Q54 NEET MCQ
10 Mar 2026
The rate constants k1 and k2 for two different reactions are 1016 $ \cdot $ e$-$2000/T and 1015 $ \cdot $ e$-$1000/T, respectively.
The temperature at which k1 = k2 is
A.
2000 K
B.
${{1000} \over {2.303}}K$
C.
1000 K
D.
${{2000} \over {2.303}}K$
2008 Q55 NEET MCQ
10 Mar 2026
The bromination of acetone that occurs in acid solution is represented by this equation.
CH3COCH3(aq) + Br2(aq)  $ \to $
     CH3COCH2Br(aq) + H+(aq) + Br$-$(aq)
These kinetic data were obtained for given reaction concentrations.
Initial concentrations, M
[CH3COCH3 [Br2] [H+]
0.30 0.05 0.05
0.30 0.10 0.05
0.30 0.10 0.10
0.40 0.05 0.20

Initial rate, disappearance of Br2, Ms$-$1
5.7$ \times $10$-$5
5.7$ \times $10$-$5
1.2$ \times $10$-$4
3.1$ \times $10$-$4

Based on these data, the rate equation is
A.
Rate = k[CH3COCH3][Br2][H+]2
B.
Rate = k[CH3COCH3][Br2][H+]
C.
Rate = k[CH3COCH3][H+]
D.
Rate = k[CH3COCH3][Br2]
2007 Q56 NEET MCQ
10 Mar 2026
The reaction of hydrogen and iodine monochloride is given as :
H2(g) + 2ICl(g) $ \to $ 2HCl(g) + I2(g)
This reaction is of first order with respect to H2(g) and ICl(g),
following mechanisms were proposed.

Mechanism A :
     H2(g) + 2ICl(g) $ \to $ 2HCl(g) + I2(g)
Mechanism B :
     H2(g) + ICl(g) $ \to $ HCl(g) + HI(g) ; slow
     HI(g) + ICl(g) $ \to $ HCl(g) + I2(g) ; fast

Which of the above mechanism(s) can be consistent with the given information about the reaction?
A.
A and B both
B.
Neither A nor B
C.
A only
D.
B only
2007 Q57 NEET MCQ
10 Mar 2026
In a first-order reaction A $ \to $ B, if k is rate constant and initial concentration of the reactant A is 0.5 M, then the half-life is
A.
${{\log 2} \over k}$
B.
${{\log 2} \over {k\sqrt {0.5} }}$
C.
${{\ln 2} \over k}$
D.
${{0.693} \over {0.5k}}$
2007 Q58 NEET MCQ
10 Mar 2026
If 60% of a first order reaction was completed in 60 minutes, 50% of the same reaction would be completed in approximately
(log 4 = 0.60, log 5 = 0.69)
A.
45 minutes
B.
60 minutes
C.
40 minutes
D.
50 minutes
2006 Q59 NEET MCQ
10 Mar 2026
For the reaction, 2A + B $ \to $ 3C + D, which of the following does not express the reaction rate?
A.
$ - {{d\left[ A \right]} \over {2dt}}$
B.
$ - {{d\left[ C \right]} \over {3dt}}$
C.
$ - {{d\left[ B \right]} \over {dt}}$
D.
$ {{d\left[ D \right]} \over {dt}}$
2006 Q60 NEET MCQ
10 Mar 2026
Consider the reaction :  N2(g) + 3H2(g) $ \to $ 2NH3(g)

The equality relationship between ${{d\left[ {N{H_3}} \right]} \over {dt}}$ and $ - {{d\left[ {{H_2}} \right]} \over {dt}}$ is
A.
${{d\left[ {N{H_3}} \right]} \over {dt}} = - {{d\left[ {{H_2}} \right]} \over {dt}}$
B.
${{d\left[ {N{H_3}} \right]} \over {dt}} = - {1 \over 3}{{d\left[ {{H_2}} \right]} \over {dt}}$
C.
$ + {{d\left[ {N{H_3}} \right]} \over {dt}} = - {2 \over 3}{{d\left[ {{H_2}} \right]} \over {dt}}$
D.
$ + {{d\left[ {N{H_3}} \right]} \over {dt}} = - {3 \over 2}{{d\left[ {{H_2}} \right]} \over {dt}}$
2005 Q61 NEET MCQ
10 Mar 2026
The rate of reaction between two reactions A and B decreases by a factor of 4 if the concentration of reactant B is doubled. The order of this reaction with respect to reactant B is
A.
2
B.
$-$2
C.
1
D.
$-$1
2005 Q62 NEET MCQ
10 Mar 2026
For a first order reaction A $ \to $ B the reaction rate a reactant concentration of 0.01 M is found to be 2.0 $ \times $ 10$-$5 mol L$-$1 s$-$1. The half-life period of the reaction is
A.
30 s
B.
220 s
C.
300 s
D.
347 s
2004 Q63 NEET MCQ
10 Mar 2026
The rate of a first order reaction is 1.5 $ \times $ 10$-$2 mol L$-$1 min$-$1 at 0.5 M concentration of the reactant. The half-life of the reaction is
A.
0.383 min
B.
23.1 min
C.
8.73 min
D.
7.53 min
2003 Q64 NEET MCQ
10 Mar 2026
The reaction A $ \to $ B follows first order kinetics. The time taken for 0.8 mole of A to produce 0.6 mole of B is 1 hour. What is the time taken for conversion of 0.9 mole of A to produce 0.675 mole of B?
A.
1 hour
B.
0.5 hour
C.
0.25 hour
D.
2 hours
2003 Q65 NEET MCQ
10 Mar 2026
The temperature dependence of rate constant (k) of a chemical reaction is written in terms of Arrhenius equation, $k = A \cdot {e^{ - E{}^ * /RT}}$. Activation energy (E$ * $) of the reaction can be calculated by plotting
A.
$k\,\,vs\,\,T$
B.
$k\,\,vs\,\,{1 \over {\log T}}$
C.
$\log \,k\,\,vs\,\,{1 \over T}$
D.
$\log \,k\,\,vs\,{1 \over {\log T}}$
2003 Q66 NEET MCQ
10 Mar 2026
The activation energy for a simple chemical reaction A $\rightleftharpoons$ B is E$a$ in forward direction.
The activation energy for reverse reaction
A.
is negative of E$a$
B.
is always less than E$a$
C.
can be less than or more than E$a$
D.
is always double of E$a$
2003 Q67 NEET MCQ
10 Mar 2026
If the rate of the reaction is equal to the rate constant, the order of the reaction is
A.
0
B.
1
C.
2
D.
3
2002 Q68 NEET MCQ
10 Mar 2026
2A $ \to $ B + C

It would be a zero order reaction when
A.
the rate of reaction is proportional to square of concentration of A
B.
The rate of reaction remains same at any concentration of A
C.
the rate remains unchanged at any concentration of B and C
D.
the rate of reaction doubles if concentrations of B is increased to double.
2001 Q69 NEET MCQ
10 Mar 2026
For the reaction;

2N2O5 $ \to $ 4NO2 + O2 rate and rate constant are 1.02 $ \times $ 10$-$4 and 3.4 $ \times $ 10$-$5 sec$-$1 respectively, then concentration of N2O5 at that time will be
A.
1.732
B.
3
C.
1.02 $ \times $ 10$-$4
D.
3.4 $ \times $ 105
2001 Q70 NEET MCQ
10 Mar 2026
When a bio-chemical reaction is carried out in laboratory, outside the human body in absence of enzyme, then rate of reaction obtained is 10$-$6 times, the activation energy of reaction in the presence of enzyme is
A.
6/RT
B.
P is required
C.
different from E$a$ obtained in laboratory
D.
can't say anything.
2000 Q71 NEET MCQ
10 Mar 2026
For the reaction H+ + BrO$_3^ - $ + 3Br$-$ $ \to $ 5Br2 + H2O
which of the following relation correctly represents the consumption and formation of products.
A.
${{d\left[ {B{r^ - }} \right]} \over {dt}} = - {3 \over 5}{{d\left[ {B{r_2}} \right]} \over {dt}}$
B.
${{d\left[ {B{r^ - }} \right]} \over {dt}} = {3 \over 5}{{d\left[ {B{r_2}} \right]} \over {dt}}$
C.
${{d\left[ {B{r^ - }} \right]} \over {dt}} = - {5 \over 3}{{d\left[ {B{r_2}} \right]} \over {dt}}$
D.
${{d\left[ {B{r^ - }} \right]} \over {dt}} = {5 \over 3}{{d\left[ {B{r_2}} \right]} \over {dt}}$
2000 Q72 NEET MCQ
10 Mar 2026
How enzymes increases the rate of reactions
A.
by lowering activation energy
B.
by increaing activation energy
C.
by changing equilibrium constant
D.
by forming enzyme substrate complex.