How many questions from Chemical Kinetics appear in JEE?

Chemical Kinetics has appeared in 169 of the last 186 JEE Main and JEE Advanced papers — about 91% of them — contributing 188 questions in total across those papers.

Is Chemical Kinetics an important chapter for JEE?

Judged by how often it is actually tested, it appears in roughly 91% of papers. Chapters above about 50% are effectively guaranteed to show up every session, so they repay thorough preparation; lower-frequency chapters are better treated as targeted revision.

Where do these Chemical Kinetics questions come from?

Every question is from an official JEE Main or JEE Advanced paper, transcribed from the original paper and tagged to this chapter. Answers follow the official answer key.

Chemical Kinetics JEE Previous Year Questions with Answers

Q1·ChemistryMultiple correctJEE Advanced 2026

For a first-order reaction R

\longrightarrow

P at a given temperature,

k

is the rate constant. For this reaction, at the given temperature, the concentrations of R and P at a time

t

are [R] and [P], respectively. The correct graphical representation(s) for this reaction is(are)

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q2·ChemistrySingle correctJEE Advanced 2026

For a reversible reaction R ⇌ P, at constant temperature, both the forward and the backward reactions are first order elementary reactions with rate constants

k_f

and

k_b

, respectively. At time zero, the concentration of R is

[\mathrm{R}]_0

and the concentration of P is zero. At any given time, [R] and [P] are the concentrations of R and P, respectively. If

k_b = 4k_f

, the correct graphical representation of the reaction is

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q3·ChemistrySingle correctJEE Main 2026

Given below are two statements:

R = 8.314

J K

^{-1}

mol

^{-1}

and 1 cal

= 4.2

J Statement I: When

E_a = 12.6

kcal/mol, the room temperature rate constant is doubled by a

10\,^{\circ}

C increase in temperature (298 K to 308 K) Statement II: For a first order reactions A

\rightarrow

B, Here

[A]_o

is the initial concentration of A and

t_{1/2}

is half life of reaction. In the light of the above statements, choose the correct answer from the options given below:

(A)Both Statement I and Statement II are true
(B)Both Statement I and Statement II are false
(C)Statement I is true but Statement II is false
(D)Statement I is false but Statement II is true

Q4·ChemistryNumericalJEE Main 2026

Sucrose hydrolyses in acidic medium into glucose and fructose by first order rate law with

t_{1/2} = 3

hour. The percentage of sucrose remaining after 6 hours is _______. (Nearest integer) (Given: log 2 = 0.3010 and log 3 = 0.4771)

Q5·ChemistryNumericalJEE Main 2026

Decomposition of a hydrocarbon follows the equation

k = (5.5 \times 10^{11}\ \mathrm{s^{-1}})\, e^{\frac{-28000\ \mathrm{K}}{T}}

. The activation energy of reaction is __________ kJ mol

^{-1}

. (Nearest Integer) Given : R = 8.3 J K

^{-1}

mol

^{-1}

Q6·ChemistryNumericalJEE Main 2026

If the half life of a first order reaction is 6.93 minutes then the time required for completion of 99% of the reaction will be _____ minutes. (Given :

\log 2 = 0.3010

)

Q7·ChemistrySingle correctJEE Main 2026

First order gas phase reaction

A \rightarrow B + C

p_i

= initial pressure of gas A,

p_t

= total pressure of the reaction mixture at time

t

Expression of rate constant (

k

) is

(A) $\frac{1}{t} \ln \frac{p_i}{2p_i - p_t}$
(B) $\frac{1}{t} \ln \frac{2p_i}{p_i - p_t}$
(C) $\frac{1}{t} \ln \frac{p_i}{3p_i - 2p_t}$
(D) $\frac{1}{t} \ln \frac{3p_i}{4p_i - p_t}$

Q8·ChemistryNumericalJEE Main 2026

For a reaction A → P at T K, the half life (t₁/₂) is plotted as a function of initial concentration [A]₀ of A as given below. The value of x in the given figure is _______ s (Nearest integer)

Q9·ChemistrySingle correctJEE Main 2026

Consider the given graph showing variation of reactant concentration with time. Three different reactions were started with identical initial concentration of reactants. Which of the following statement is correct?

(A)The order of all the three reactions is same.
(B)The rate constant of reaction 3 is larger than the rate constant of reaction 2 if the order of reaction is same for both.
(C)The SI unit of rate constant of reaction 1 is $\mathrm{s^{-1}}$ .
(D)Thermal decomposition of HI on gold surface is an example of reaction 2.

Q10·ChemistryNumericalJEE Main 2026

For a first order reaction

A \rightarrow B

x

= ______ min. (Nearest integer)

$t$ /min	$[A]$ /M
0	0.6500
$x$	0.0650
20	0.00065

Q11·ChemistrySingle correctJEE Main 2026

Consider the first order reaction

R \rightarrow P

. The fraction of molecules decomposed in the given first order reaction can be expressed as

(A) $1 - e^{k_1 t}$
(B) $1 + e^{k_1 t}$
(C) $1 + e^{-k_1 t}$
(D) $1 - e^{-k_1 t}$

Q12·ChemistrySingle correctJEE Main 2026

t_{100\%}

is the time required for the 100% completion of the reaction while

t_{1/2}

is the time required for 50% of the reaction to be completed. Which of the following option correctly represents the relation between

t_{100\%}

and

t_{1/2}

for zero and first order reactions respectively?

(A) $t_{100\%} = (t_{1/2})^{2}$ and $t_{100\%} = (t_{1/2})^{-\infty}$
(B) $t_{100\%} = 2t_{1/2}$ and $t_{100\%} = (t_{1/2})^{\infty}$
(C) $t_{100\%} = 2t_{1/2}$ and $t_{100\%} = (2t_{1/2})^{2}$
(D) $t_{100\%} = (t_{1/2})^{\infty}$ and $t_{100\%} = 2t_{1/2}$

Q13·ChemistryNumericalJEE Main 2026

Consider the following gas phase reaction being carried out in a closed vessel at

25^\circ C

.

2A(g) \rightarrow 4B(g) + C(g)

The pressure of

C(g)

at 30 minutes time interval would be ________ mm Hg. (nearest integer)

time (min)	total pressure of the system (mm Hg)
30	300
$\infty$	600

Q14·ChemistrySingle correctJEE Main 2026

Consider the reaction

aX \rightarrow bY

, for which the rate constant at

30^{\circ}C

is

1 \times 10^{-3}

mol

^{-1}

L s

^{-1}

. Which of the following statements are true? A. When concentration of 'X' is increased to four times, the rate of reaction becomes 16 times. B. The reaction is a second order reaction. C. The half-life period is independent of the concentration of X. D. Decomposition of

N_2O_5

is an example of the above reaction. E.

\ln \frac{[R_o]}{[R]}

vs time is valid for the above reaction. Choose the correct answer from the options given below:

(A)A and B Only
(B)A, B and C Only
(C)A, B, D and E Only
(D)C and D Only

Q15·ChemistryNumericalJEE Main 2026

For reaction

A\rightarrow P

, rate constant

k=1.5\times 10^{3}\ \mathrm{s^{-1}}

at

27\,^{\circ}\mathrm{C}

. If activation energy for the above reaction is 60 kJ

\mathrm{mol^{-1}}

, then the temperature (in °C) at which rate constant,

k=4.5\times 10^{3}\ \mathrm{s^{-1}}

is ________. (Nearest integer) Given :

\log 2=0.30

,

\log 3=0.48

,

R=8.3\ \mathrm{J\,K^{-1}\,mol^{-1}}

,

\ln 10=2.3

Q16·ChemistrySingle correctJEE Main 2026

An organic compound undergoes first order decomposition. The time taken for decomposition to

\left(\dfrac{1}{8}\right)^{th}

and

\left(\dfrac{1}{10}\right)^{th}

of its initial concentration are t

_{1/8}

and t

_{1/10}

respectively. What is the value of

\dfrac{\text{t}_{1/8}}{\text{t}_{1/10}} \times 10

? (log 2 = 0.3)

(A)9
(B)0.9
(C)3
(D)30

Q17·ChemistryNumericalJEE Main 2026

A \rightarrow B

(first reaction)

C \rightarrow D

(second reaction) Consider the above two first-order reactions. The rate constant for first reaction at 500 K is double of the same at 300 K. At 500 K, 50% of the reaction becomes complete in 2 hour. The activation energy of the second reaction is half of that of first reaction. If the rate constant at 500 K of the second reaction becomes double of the rate constant of first reaction at the same temperature; then rate constant for the second reaction at 300 K is ________

\times 10^{-1}

hour^{-1}

(nearest integer).

Q18·ChemistryNumericalJEE Main 2026

The half-life of

^{65}\text{Zn}

is 245 days. After x days, 75% of original activity remained. The value of x in days is _______ . (Nearest integer) (Given : log 3 = 0.4771 and log 2 = 0.3010)

Q19·ChemistrySingle correctJEE Main 2026

At 27°C in presence of a catalyst, activation energy of a reaction is lowered by 10 kJ mol

^{-1}

. The logarithm ratio of

\dfrac{\mathrm{k}\left(\text{catalysed}\right)}{\mathrm{k}\left(\text{uncatalysed}\right)}

is .... (Consider that the frequency factor for both the reactions is same)

(A)17.41
(B)1.741
(C)3.482
(D)0.1741

Q20·ChemistrySingle correctJEE Main 2026

A → D is an endothermic reaction occurring in three steps (elementary). (i) A → B

\Delta H_i

= +ve (ii) B → C

\Delta H_{ii}

= –ve (iii) C → D

\Delta H_{iii}

= –ve Which of the following graphs between potential energy (y-axis) vs reaction coordinate (x-axis) correctly represents the reaction profile of A → D ?

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q21·ChemistrySingle correctJEE Main 2026

Given above is the concentration vs time plot for a dissociation reaction : A → nB. Based on the data of the initial phase of the reaction (initial 10 min), the value of n is ________.

(A)4
(B)3
(C)2
(D)5

Q22·ChemistryNumericalJEE Main 2026

For the thermal decomposition of reaction AB(g), the following is constructed. The half life of the reaction is 'x' min. x = ______ min. (Nearest integer)

Q23·ChemistrySingle correctJEE Main 2026

Observe the following reactions at T(K) I. A → products. II. 5Br

^{-}

(aq) + BrO

_{3}^{-}

(aq) + 6H

^{+}

(aq) → 3Br

_{2}

(aq) + 3H

_{2}

O(

l

) Both the reactions are started at 10.00 am. The rates of these reactions at 10.10 am are same. The value of

-\frac{\Delta[\mathrm{Br}^{-}]}{\Delta \mathrm{t}}

at 10.10 am is 2 × 10

^{-4}

mol L

^{-1}

Min

^{-1}

. The concentration of A at 10.10 am is 10

^{-2}

mol L

^{-1}

. What is the first order rate constant (in min

^{-1}

) of reaction I?

(A)2 × 10 $^{-3}$
(B)10 $^{-3}$
(C)10 $^{-2}$
(D)4 × 10 $^{-3}$

Q24·ChemistrySingle correctJEE Main 2026

Correct statements regarding Arrhenius equation among the following are : (A) Factor

e^{-Ea/RT}

corresponds to fraction of molecules having kinetic energy less than Ea. (B) At a given temperature, lower the Ea, faster is the reaction. (C) Increase in temperature by about

10^\circ C

doubles the rate of reaction. (D) Plot of log k vs

\frac{1}{T}

gives a straight line with slope

= -\frac{Ea}{R}

. Choose the correct answer from the options given below :

(A)B and D only
(B)A and B only
(C)A and C only
(D)B and C only

Q25·ChemistryNumericalJEE Main 2026

Consider A

\xrightarrow{k_{1}}

B and C

\xrightarrow{k_{2}}

D are two reactions. If the rate constant

(k_{1})

of the A

\rightarrow

B reaction can be expressed by the following equation

\log_{10} k = 14.34 - \frac{1.5 \times 10^{4}}{T/K}

and activation energy of C

\rightarrow

D reaction

(Ea_{2})

is

\frac{1}{5}

th of the A

\rightarrow

B reaction

(Ea_{1})

, then the value of

(Ea_{2})

is ______ kJ

mol^{-1}

. (Nearest Integer)

Q26·ChemistrySingle correctJEE Main 2026

A → products (First order reaction). Three sets of experiment were performed for a reaction under similar experimental conditions. Run 1 ⇒ 100 mL of 10 M solution of reactant A Run 2 ⇒ 200 mL of 10 M solution of reactant A Run 3 ⇒ 100 mL of 10 M solution of reactant A+ 100 mL of H

_2

O added. The correct variation of rate of reaction is

(A)Run 1 = Run 2 = Run 3
(B)Run 3 < Run 1 = Run 2
(C)Run 3 < Run 1 < Run 2
(D)Run 1 < Run 2 < Run 3

Q27·ChemistryNumericalJEE Main 2026

The temperature at which the rate constants of the given below two gaseous reactions become equal is ________ K. (Nearest integer). X ⟶ Y

k_1 = 10^6 e^{\frac{-30000}{T}}

P ⟶ Q

k_2 = 10^4 e^{\frac{-24000}{T}}

Given : ln 10 = 2.303

Q28·ChemistryNumericalJEE Main 2026

Pre-exponential factors of two different reactions of same order are identical. Let activation energy of first reaction exceeds the activation energy of second reaction by 20 kJ mol

^{-1}

. If k

_1

and k

_2

are the rate constants of first and second reaction respectively at 300 K, then In

\frac{k_2}{k_1}

will be …….. . (nearest integer) [R=8.3 J K

^{-1}

mol

^{-1}

]

Q29·ChemistrySingle correctJEE Main 2026

Decomposition of A is a first order reaction at T(K) and is given by

\text{A(g)} \rightarrow \text{B(g)} + \text{C(g)}

. In a closed 1 L vessel, 1 bar A(g) is allowed to decompose at T(K). After 100 minutes, the total pressure was 1.5 bar. What is the rate constant (in

\text{min}^{-1}

) of the reaction ? (log 2 = 0.3)

(A) $6.9 \times 10^{-1}$
(B) $6.9 \times 10^{-3}$
(C) $6.9 \times 10^{-2}$
(D) $6.9 \times 10^{-4}$

Q30·ChemistryNumericalJEE Advanced 2025

Consider a reaction

A + R \rightarrow

Product. The rate of this reaction is measured to be

k

[

A

][

R

]. At the start of the reaction, the concentration of

R

, [

R

]

_{o}

, is 10-times the concentration of

A

, [

A

]

_{o}

. The reaction can be considered to be a pseudo first order reaction with assumption that

k

[

R

] =

k'

is constant. Due to this assumption, the relative error (in %) in the rate when this reaction is 40% complete, is ______. [

k

and

k'

represent corresponding rate constants]

Q31·ChemistrySingle correctJEE Main 2025

In a first order decomposition reaction, the time taken for the decomposition of reactant to one fourth and one eighth of its initial concentration are

t_1

and

t_2

(s), respectively. The ratio

\dfrac{t_1}{t_2}

will:

(A) $\dfrac{4}{3}$
(B) $\dfrac{3}{2}$
(C) $\dfrac{3}{4}$
(D) $\dfrac{2}{3}$

Q32·ChemistrySingle correctJEE Main 2025

A(g)\rightarrow B(g)+C(g)

is a first order reaction. The reaction was started with reactant A only. The total pressure of the system is

P_t

at time

t

and

P_\infty

at the end of the reaction (

t=\infty

). Which of the following expression is correct for the rate constant

k

?

(A) $k=\dfrac{1}{t}\ln\dfrac{2(P_\infty-P_t)}{P_t}$
(B) $k=\dfrac{1}{t}\ln\dfrac{P_\infty}{P_t}$
(C) $k=\dfrac{1}{t}\ln\dfrac{P_\infty}{2(P_\infty-P_t)}$
(D) $k=\dfrac{1}{t}\ln\dfrac{P_\infty}{(P_\infty-P_t)}$

Q33·ChemistrySingle correctJEE Main 2025

A person's wound was exposed to some bacteria and then bacteria growth started to happen at the same place. The wound was later treated with some antibacterial medicine and the rate of bacterial decay (r) was found to be proportional with the square of the existing number of bacteria at any instance. Which of the following set of graphs (shown in the figure) correctly represents the 'before' and 'after' situation of the application of the medicine? (Given: N = No. of bacteria, t = time, bacterial growth follows 1st order kinetics.)

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q34·ChemistrySingle correctJEE Main 2025

Reaction

A(g)\to2B(g)+C(g)

is a first order reaction. It was started with pure A. The pressure of the system is 160 mm Hg at

t=10

min and 240 mm Hg at

t=\infty

. Which of the following option is incorrect?

(A)Initial pressure of A is 80 mm Hg
(B)The reaction never goes to completion
(C)Rate constant of the reaction is 1.693 min $^{-1}$
(D)Partial pressure of A after 10 minute is 40 mm Hg

Q35·ChemistrySingle correctJEE Main 2025

Half life of zero order reaction

A \rightarrow

product is 1 hour, when initial concentration of reactant is

2.0\ mol\,L^{-1}

. The time required to decrease concentration of A from 0.50 to

0.25\ mol\,L^{-1}

is:

(A)0.5 hour
(B)4 hour
(C)15 min
(D)60 min

Q36·ChemistrySingle correctJEE Main 2025

Consider the following plots of log of rate constant (

\log k

) vs

1/T

for three different reactions. The correct order of activation energies of these reactions is:

(A) $Ea_2 > Ea_1 > Ea_3$
(B) $Ea_1 > Ea_3 > Ea_2$
(C) $Ea_1 > Ea_2 > Ea_3$
(D) $Ea_3 > Ea_2 > Ea_1$

Q37·ChemistrySingle correctJEE Main 2025

Rate law for a reaction between A and B is given by

R=k[A]^n[B]^m

. If concentration of A is doubled and concentration of B is halved from their initial value, the ratio of new rate of reaction to the initial rate of reaction

\left(\dfrac{r_2}{r_1}\right)

is:

(A) $2^{(n-m)}$
(B) $(n-m)$
(C) $(m+n)$
(D) $\dfrac{1}{2^{m+n}}$

Q38·ChemistrySingle correctJEE Main 2025

For

A_2+B_2\rightleftharpoons 2AB

,

E_a

for forward and backward reaction are 180 and 200 kJ mol

^{-1}

respectively. If catalyst lowers

E_a

for both reaction by 100 kJ mol

^{-1}

. Which of the following statement is correct?

(A)Catalyst does not alter the Gibbs energy change of a reaction.
(B)Catalyst can cause non-spontaneous reactions to occur.
(C)The enthalpy change for the reaction is $+20$ kJ mol $^{-1}$ .
(D)The enthalpy change for the catalysed reaction is different from that of uncatalysed reaction.

Q39·ChemistrySingle correctJEE Main 2025

Consider the following statements related to temperature dependence of rate constants. Identify the correct statements: A. The Arrhenius equation holds true only for an elementary homogeneous reaction. B. The unit of A is same as that of k in Arrhenius equation. C. At a given temperature, a low activation energy means a fast reaction. D. A and

E_a

as used in Arrhenius equation depend on temperature. E. When

E_a \gg RT

, A and

E_a

become interdependent. Choose the correct answer from the options given below:

(A)A, C and D Only
(B)B, D and E Only
(C)B and C Only
(D)A and B Only

Q40·ChemistrySingle correctJEE Main 2025

In a reaction

A+B\to C

, initial concentrations of A and B are related as

[A]_0=8[B]_0

. The half lives of A and B are 10 min and 40 min respectively. If they start to disappear at the same time, both following first order kinetics, after how much time will the concentration of both the reactants be same?

(A)60 min
(B)80 min
(C)20 min
(D)40 min

Q41·ChemistryIntegerJEE Main 2025

For the reaction

A\to B

the following graph was obtained. The time required (in seconds) for the concentration of A to reduce to

2.5\ g\,L^{-1}

(if the initial concentration of A was

50\ g\,L^{-1}

) is ______. (Nearest integer) [Given:

\log 2=0.3010

]

Q42·ChemistryIntegerJEE Main 2025

For the reaction A → products, a plot of half-life

t_{1/2}

/min versus initial concentration

[A]_0

/mol L

^{-1}

(shown in the figure) is a straight line with slope 76.92 (appropriate units). The concentration of A at 10 minutes is ______

\times10^{-3}

mol L

^{-1}

(nearest integer). The reaction was started with 2.5 mol L

^{-1}

of A.

Q43·ChemistrySingle correctJEE Main 2025

Reactant A converts to product D through the following mechanism (with the net evolution of heat):

A\to B

slow,

\Delta H=+ve

;

B\to C

fast,

\Delta H=-ve

;

C\to D

fast,

\Delta H=-ve

. Which of the following represents the above reaction mechanism?

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q44·ChemistrySingle correctJEE Main 2025

The reaction

A_2+B_2\rightarrow 2AB

follows the mechanism:

A_2\underset{k_{-1}}{\overset{k_1}{\rightleftharpoons}}A+A

(fast);

A+B_2\xrightarrow{k_2}AB+B

(slow);

A+B\rightarrow AB

(fast). The overall order of the reaction is:

(A)1.5
(B)3
(C)2.5
(D)2

Q45·ChemistrySingle correctJEE Main 2025

Drug X becomes ineffective after 50% decomposition. The original concentration of drug in a bottle was 16 mg/mL which becomes 4 mg/mL in 12 months. The expiry time of the drug in months is ______. Assume that the decomposition of the drug follows first order kinetics.

(A)12
(B)2
(C)3
(D)6

Q46·ChemistrySingle correctJEE Main 2025

Consider the elementary reaction A(g) + B(g)

\to

C(g) + D(g). If the volume of reaction mixture is suddenly reduced to

\frac{1}{3}

of its initial volume, the reaction rate will become 'x' times of the original reaction rate. The value of x is:

(A) $\frac{1}{9}$
(B)9
(C) $\frac{1}{3}$
(D)3

Q47·ChemistrySingle correctJEE Main 2025

For bacterial growth in a cell culture, growth law is very similar to the law of radioactive decay. Which of the following graphs is most suitable to represent bacterial colony growth?

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q48·ChemistrySingle correctJEE Main 2025

\begin{array}{cc}[A]_0/molL^{-1} & t_{1/2}/min\\ 0.100 & 200\\ 0.025 & 100\end{array}

For a given reaction R

\to

P,

t_{1/2}

is related to

[A]_0

as given in table. Given:

\log 2=0.30

. Which of the following is true? A. The order of the reaction is

\frac{1}{2}

. B. If

[A]_0

is 1M,

t_{1/2}

is

200\sqrt{10}

min. C. The order of the reaction changes to 1 if the concentration of reactant changes from 0.100 M to 0.500 M. D.

t_{1/2}

is 800 min for

[A]_0=1.6

M. Choose the correct answer from the options given below:

(A)A and C only
(B)A and B only
(C)A, B and D only
(D)C and D only

Q49·ChemistryIntegerJEE Main 2025

Consider a complex reaction taking place in three steps with rate constants

k_1

,

k_2

and

k_3

respectively. The overall rate constant k is given by the expression

k=\sqrt{\dfrac{k_1k_3}{k_2}}

. If the activation energies of the three steps are 60, 30 and 10 kJ mol

^{-1}

respectively, then the overall energy of activation in kJ mol

^{-1}

is __________. (Nearest integer)

Q50·ChemistrySingle correctJEE Main 2025

Given below are two statements: Statement (I): A plot of half-life

t_{1/2}

versus initial concentration

[R]_0

is a horizontal straight line — is valid for first order reaction. Statement (II): A plot of

\log\dfrac{[R]}{[R]_0}

versus time is a straight line with slope

\dfrac{k}{2.303}

— is valid for first order reaction. In the light of the above statements, choose the correct answer from the options given below :

(A)Both Statement I and Statement II are false
(B)Statement I is false but Statement II is true
(C)Both Statement I and Statement II are true
(D)Statement I is true but Statement II is false

Q51·ChemistrySingle correctJEE Main 2025

For a reaction,

N_2O_5(g)\to 2NO_2(g)+\dfrac{1}{2}O_2(g)

in a constant volume container, no products were present initially. The final pressure of the system when 50% of reaction gets completed is

(A) $\dfrac{7}{2}$ times of initial pressure
(B)5 times of initial pressure
(C) $\dfrac{5}{2}$ times of initial pressure
(D) $\dfrac{7}{4}$ times of initial pressure

Q52·ChemistrySingle correctJEE Main 2025

Which of the following graphs most appropriately represents a zero order reaction?

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q53·ChemistryIntegerJEE Main 2025

For the thermal decomposition of N₂O₅(g) at constant volume, the following table can be formed, for the reaction

2N_2O_5(g)\rightarrow 2N_2O_4(g)+O_2(g)

. (Table — S.No. 1: Time = —, Total pressure = 0.6 atm; S.No. 2: Time = 100 s, Total pressure = x).

x=

_______

\times10^{-3}

atm [nearest integer]. (Given: Rate constant for the reaction is

4.606\times10^{-2}

s

^{-1}

.)

Q54·ChemistryIntegerJEE Main 2025

A molecule A changes into its isomeric form B by first-order kinetics at 1000 K. If the energy barrier with respect to the reactant is 191.48 kJ mol⁻¹ and the frequency factor is 10²⁰, the time required for 50% of A to convert to B is ______ picoseconds (nearest integer). (R = 8.314 J K⁻¹ mol⁻¹)

Q55·ChemistrySingle correctJEE Main 2025

Consider the given figure and choose the correct option:

(A)Activation energy of backward reaction is $E_1$ and product is more stable than reactant.
(B)Activation energy of forward reaction is $E_1+E_2$ and product is more stable than reactant.
(C)Activation energy of forward reaction is $E_1+E_2$ and product is less stable than reactant.
(D)Activation energy of both forward and backward reaction is $E_1+E_2$ and reactant is more stable than product.

Q56·ChemistrySingle correctJEE Main 2025

Which of the following statements is NOT true for radioactive decay?

(A)The amount of radioactive substance remaining after three half-lives is 1/8th of the original amount
(B)The decay constant does not depend upon temperature
(C)The decay constant increases with increase in temperature
(D)Half-life is 0.693 times (1/rate constant)

Q57·ChemistryIntegerJEE Advanced 2024

Consider the following reaction,

2\mathrm{H}_{2}(g) + 2\mathrm{NO}(g) \longrightarrow \mathrm{N}_{2}(g) + 2\mathrm{H}_{2}\mathrm{O}(g)

Which follows the mechanism given below?

2\mathrm{NO}(g) \underset{\mathrm{K}_{-1}}{\overset{\mathrm{K}_{1}}{\rightleftharpoons}} \mathrm{N}_{2}\mathrm{O}_{2}(g)

(fast equilibrium)

\mathrm{N}_{2}\mathrm{O}_{2}(g) + \mathrm{H}_{2}(g) \xrightarrow{\mathrm{k}_{2}} \mathrm{N}_{2}\mathrm{O}(g) + \mathrm{H}_{2}\mathrm{O}(g)

(slow reaction)

\mathrm{N}_{2}\mathrm{O}(g) + \mathrm{H}_{2}(g) \xrightarrow{\mathrm{k}_{3}} \mathrm{N}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(g)

(fast reaction) The order of the reaction is _________.

Q58·ChemistryNumericalJEE Main 2024

Given below are two statements: Statement I: The rate law for the reaction

A + B \rightarrow C

is rate

(r) = k[A]^2[B]

. When the concentration of both A and B is doubled, the reaction rate is increased "x" times. Statement II: The figure is showing "the variation in concentration against time plot" for a "y" order reaction. The value of x + y is _____.

Q59·ChemistryNumericalJEE Main 2024

Consider the following first order gas phase reaction at constant temperature:

A(g)\rightarrow 2B(g)+C(g)

. If the total pressure of the gases is found to be 200 torr after 23 sec and 300 torr upon the complete decomposition of A after a very long time, then the rate constant of the given reaction is _______

\times10^{-2}

s

^{-1}

(nearest integer). [Given:

\log_{10}(2)=0.301

]

Q60·ChemistryNumericalJEE Main 2024

Consider the reaction

A+B\to C

. The time taken for

A

to become

\dfrac14^{th}

of its initial concentration is twice the time taken to become

\dfrac12

of the same. Also, when the change of concentration of

B

is plotted against time, the resulting graph gives a straight line with a negative slope and a positive intercept on the concentration axis. The overall order of the reaction is ___

Q61·ChemistrySingle correctJEE Main 2024

For a reaction

A\xrightarrow{K_1}B\xrightarrow{K_2}C

, if the rate of formation of B is set to be zero then the concentration of B is given by:

(A) $K_1K_2[A]$
(B) $(K_1-K_2)[A]$
(C) $(K_1+K_2)[A]$
(D) $\left(\dfrac{K_1}{K_2}\right)[A]$

Q62·ChemistryNumericalJEE Main 2024

Consider the two different first order reactions given below:

A + B \rightarrow C

(Reaction 1) and

P \rightarrow Q

(Reaction 2). The ratio of the half life of Reaction 1 : Reaction 2 is 5 : 2. If

t_1

and

t_2

represent the time taken to complete

\frac{2}{3}^{rd}

of Reaction 1 and

\frac{4}{5}^{th}

of Reaction 2, respectively, then the value of the ratio

t_1 : t_2

is _______

\times 10^{-1}

(nearest integer). [Given:

\log_{10}(3) = 0.477

and

\log_{10}(5) = 0.699

]

Q63·ChemistryNumericalJEE Main 2024

Time required for 99.9% completion of a first order reaction is _______ times the time required for completion of 90% reaction (nearest integer).

Q64·ChemistryNumericalJEE Main 2024

Consider the following single step reaction in the gas phase at constant temperature:

2A(g) + B(g) \rightarrow C(g)

. The initial rate of the reaction is recorded as

r_1

when the reaction starts with 1.5 atm pressure of A and 0.7 atm pressure of B. After some time, the rate

r_2

is recorded when the pressure of C becomes 0.5 atm. The ratio

r_1 : r_2

is __________

\times 10^{-1}

. (Nearest integer)

Q65·ChemistryNumericalJEE Main 2024

During the kinetic study of the reaction

2A + B \rightarrow C + D

, the following results were obtained: (I)

[A]=0.1

,

[B]=0.1

, rate

=6.0\times10^{-3}

; (II)

[A]=0.3

,

[B]=0.2

, rate

=7.2\times10^{-2}

; (III)

[A]=0.3

,

[B]=0.4

, rate

=2.88\times10^{-1}

; (IV)

[A]=0.4

,

[B]=0.1

, rate

=2.40\times10^{-2}

(all rates of formation of D, in M s

^{-1}

). Based on the above data, the overall order of the reaction is ___.

Q66·ChemistryNumericalJEE Main 2024

Consider the transformation

A+B\xrightarrow{\text{Step 1}}C\xrightarrow{\text{Step 2}}P

(first order elementary reaction in each step). The rate constants and activation energies are: Step 1:

k_1

,

E_a=300\,kJ\,mol^{-1}

; Step 2:

k_2

,

E_a=200\,kJ\,mol^{-1}

; Step 3:

k_3

,

E_a=E_{a_3}

. If the overall rate constant

k=\dfrac{k_1 k_2}{k_3}

and the overall activation energy

E_a

is

400\,kJ\,mol^{-1}

, then the value of

E_{a_3}

is ___

kJ\,mol^{-1}

(nearest integer)

Q67·ChemistryNumericalJEE Main 2024

Consider the following reaction, the rate expression of which is given below

A+B\to C

, rate

=k[A]^{1/2}[B]^{1/2}

. The reaction is initiated by taking 1 M concentration A and B each. If the rate constant (k) is

4.6\times10^{-2}\ \text{s}^{-1}

, then the time taken for A to become 0.1 M is ______ sec. (nearest integer)

Q68·ChemistryNumericalJEE Main 2024

The ratio of

\dfrac{^{14}C}{^{12}C}

in a piece of wood is

\dfrac18

part that of atmosphere. If half life of

^{14}C

is

5730

years, the age of wood sample is ___ years.

Q69·ChemistryNumericalJEE Main 2024

The following data were obtained during the first order thermal decomposition of a gas A at constant volume:

\text{A}(g)\to 2\text{B}(g)+\text{C}(g)

. S.No 1:

t=0

s, Total pressure

=0.1

atm. S.No 2:

t=115

s, Total pressure

=0.28

atm. The rate constant of the reaction is __________

\times 10^{-2}

s

^{-1}

(nearest integer).

Q70·ChemistryNumericalJEE Main 2024

r=k[A]

for a reaction, 50% of A is decomposed in 120 minutes. The time taken for 90% decomposition of A is ______ minutes.

Q71·ChemistrySingle correctJEE Main 2024

Integrated rate law equation for a first order gas phase reaction is given by (where

P_i

is initial pressure and

P_t

is total pressure at time t)

(A) $k=\dfrac{2.303}{t}\times\log\dfrac{P_i}{(2P_i-P_t)}$
(B) $k=\dfrac{2.303}{t}\times\log\dfrac{2P_i}{(2P_i-P_t)}$
(C) $k=\dfrac{2.303}{t}\times\log\dfrac{(2P_i-P_t)}{P_i}$
(D) $k=\dfrac{2.303}{t}\times\dfrac{P_i}{(2P_i-P_t)}$

Q72·ChemistryNumericalJEE Main 2024

The rate of first order reaction is

0.04\,mol\,L^{-1}\,s^{-1}

at 10 minutes and

0.03\,mol\,L^{-1}\,s^{-1}

at 20 minutes after initiation. Half life of the reaction is ___ minutes. (Given

\log2=0.3010

,

\log3=0.4771

)

Q73·ChemistryNumericalJEE Main 2024

NO_2

required for a reaction is produced by decomposition of

N_2O_5

in

CCl_4

as by equation

2N_2O_5(g)\rightarrow 4NO_2(g)+O_2(g)

. The initial concentration of

N_2O_5

is 3 mol L

^{-1}

and it is 2.75 mol L

^{-1}

after 30 minutes. The rate of formation of

NO_2

is

x\times10^{-3}

mol L

^{-1}

min

^{-1}

, value of

x

is ______.

Q74·ChemistryNumericalJEE Main 2024

The half-life of radioisotope bromine-82 is 36 hours. The fraction which remains after one day is ___

\times10^{-2}

. (Given antilog 0.2006 = 1.587)

Q75·ChemistryNumericalJEE Main 2024

For a reaction taking place in three steps at same temperature, overall rate constant

K=\dfrac{K_1 K_2}{K_3}

. If

Ea_1

,

Ea_2

and

Ea_3

are 40, 50 and 60 kJ/mol respectively, the overall Ea is ______ kJ/mol.

Q76·ChemistryNumericalJEE Main 2024

Time required for completion of 99.9% of a First order reaction is __________ times of half life (

t_{1/2}

) of the reaction.

Q77·ChemistryNumericalJEE Main 2024

Consider the following data for the given reaction

2\text{HI}_{(g)}\to\text{H}_{2(g)}+\text{I}_{2(g)}

. Experiment 1, 2, 3 — [HI] (mol L

^{-1}

) = 0.005, 0.01, 0.02; Rate (mol L

^{-1}

s

^{-1}

) =

7.5\times 10^{-4}

,

3.0\times 10^{-3}

,

1.2\times 10^{-2}

. The order of the reaction is __________.

Q78·ChemistryNumericalJEE Advanced 2023

The plot of

\log k_f

versus 1/T for a reversible reaction

\mathrm{A(g)} \rightleftharpoons \mathrm{P(g)}

is shown Pre-exponential factors for the forward and backward reactions are

10^{15}\ \mathrm{s^{-1}}

and

10^{11}\ \mathrm{s^{-1}}

, respectively. If the value of

\log K

for the reaction at 500 K is 6, the value of

\left| \log k_b \right|

at 250 K is ___. [

K

= equilibrium constant of the reaction

k_f

= rate constant of forward reaction

k_b

= rate constant of backward reaction]

Q79·ChemistryNumericalJEE Main 2023

For a reversible reaction

A \rightleftharpoons B

, the

\Delta H_{forward\ reaction} = 20

kJ

mol^{-1}

. The activation energy of the uncatalysed forward reaction is 300 kJ

mol^{-1}

. When the reaction is catalysed keeping the reactant concentration same, the rate of the catalysed forward reaction at 27 C is found to be same as that of the uncatalysed reaction at 327 C. The activation energy of the catalysed backward reaction is _______ kJ

mol^{-1}

.

Q80·ChemistryNumericalJEE Main 2023

t_{87.5}

is the time required for the reaction to undergo

87.5\%

completion and

t_{50}

is the time required for the reaction to undergo

50\%

completion. The relation between

t_{87.5}

and

t_{50}

for a first order reaction is

t_{87.5}=x\times t_{50}

. The value of

x

is _____. (Nearest integer)

Q81·ChemistryNumericalJEE Main 2023

A(g) \rightarrow 2B(g) + C(g)

is a first order reaction. The initial pressure of the system was found to be 800 mm Hg which increased to 1600 mm Hg after 10 min. The total pressure of the system after 30 min will be ____ mm Hg. (Nearest integer)

Q82·ChemistryNumericalJEE Main 2023

The reaction

2NO+Br_2\rightarrow2NOBr

takes place through the mechanism given below:

NO+Br_2\rightleftharpoons NOBr_2

(fast);

NOBr_2+NO\rightarrow2NOBr

(slow). The overall order of the reaction is _________.

Q83·ChemistrySingle correctJEE Main 2023

For a chemical reaction

A+B\rightarrow

Product, the order is 1 with respect to A and B. Given the rate data — Rate (mol L

^{-1}

s

^{-1}

)/[A] (mol L

^{-1}

)/[B] (mol L

^{-1}

): row 1 =

0.10,\ 20,\ 0.5

; row 2 =

0.40,\ x,\ 0.5

; row 3 =

0.80,\ 40,\ y

. What are the values of x and y?

(A)80 and 2
(B)40 and 4
(C)160 and 4
(D)80 and 4

Q84·ChemistryNumericalJEE Main 2023

The number of incorrect statement/s from the following is _______ . A. The successive half lives of a zero order reaction decrease with time. B. A substance appearing as a reactant in the chemical equation may not affect the rate of reaction. C. Order and molecularity of a chemical reaction can be a fractional number. D. The rate constant units of zero and second order reactions are mol L

^{-1}

s

^{-1}

and mol

^{-1}

L s

^{-1}

respectively.

Q85·ChemistryNumericalJEE Main 2023

A molecule undergoes two independent first order reactions whose respective half lives are 12 min and 3 min. If both the reactions are occurring then the time taken for the 50% consumption of the reactant is _________ min. (Nearest integer)

Q86·ChemistryNumericalJEE Main 2023

The number of given statement/s which is/are correct is ____ (A) The stronger the temperature dependence of the rate constant, the higher is the activation energy. (B) If a reaction has zero activation energy, its rate is independent of temperature. (C) The stronger the temperature dependence of the rate constant, the smaller is the activation energy. (D) If there is no correlation between the temperature and the rate constant then it means that the reaction has negative activation energy.

Q87·ChemistrySingle correctJEE Main 2023

The correct reaction profile diagram for a positively catalysed reaction is:

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q88·ChemistrySingle correctJEE Main 2023

Consider the following reaction that goes from A to B in three steps as shown below. Choose the correct option.

(A)Number of intermediates: 3, Number of activated complexes: 2, Rate determining step: II
(B)Number of intermediates: 2, Number of activated complexes: 3, Rate determining step: II
(C)Number of intermediates: 2, Number of activated complexes: 3, Rate determining step: I
(D)Number of intermediates: 2, Number of activated complexes: 3, Rate determining step: III

Q89·ChemistrySingle correctJEE Main 2023

The graph which represents the following reaction is:

(C_6H_5)_3C-Cl\xrightarrow[Pyridine]{OH^-}(C_6H_5)_3C-OH

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q90·ChemistryNumericalJEE Main 2023

A\rightarrow B

. Above reaction is of zero order. Half life of this reaction is

50

min. The time taken for the concentration of A to reduce to one-fourth of its initial value is _________ (Nearest integer) min.

Q91·ChemistryNumericalJEE Main 2023

A and B are two substances undergoing radioactive decay in a container. The half life of A is 15 min and that of B is 5 min. If the initial concentration of B is 4 times that of A and they both start decaying at the same time, how much time will it take for the concentration of both of them to be same? _______ min.

Q92·ChemistryNumericalJEE Main 2023

The rate constant for a first order reaction is

20

min

^{-1}

. The time required for the initial concentration of the reactant to reduce to its

\dfrac{1}{32}

level is _________

\times10^{-2}

min. (Nearest integer) (Given: ln 10 = 2.303, log 2 = 0.3010)

Q93·ChemistryNumericalJEE Main 2023

A \rightarrow B

. The rate constants of the above reaction at

200

K and

300

K are

0.03\ min^{-1}

and

0.05\ min^{-1}

respectively. The activation energy for the reaction is ___ J (Nearest integer) (Given :

\ln 10 = 2.3

,

R = 8.3\ J\,K^{-1}\,mol^{-1}

,

\log 5 = 0.70

,

\log 3 = 0.48

,

\log 2 = 0.30

)

Q94·ChemistryNumericalJEE Main 2023

An organic compound undergoes first order decomposition. If the time taken for the 60% decomposition is 540 s, then the time required for 90% decomposition will be _______ s (nearest integer). (Given:

\ln 10=2.3

;

\log 2=0.3

)

Q95·ChemistryNumericalJEE Main 2023

If compound A reacts with B following first order kinetics with rate constant

2.011\times10^{-3}

s

^{-1}

. The time taken by A (in seconds) to reduce from

7

g to

2

g will be _________ (Nearest Integer) [log 5 = 0.698, log 7 = 0.845, log 2 = 0.301]

Q96·ChemistryNumericalJEE Main 2023

For conversion of compound

A\to B

, the rate constant of the reaction was found to be

4.6\times10^{-5}\,L\,mol^{-1}\,s^{-1}

. The order of the reaction is _____.

Q97·ChemistryNumericalJEE Main 2023

For certain chemical reaction X

\rightarrow

Y, the rate of formation of product is plotted against the time as shown in the figure. The number of correct statement/s from the following is ________ . (A) Over all order of this reaction is one (B) Order of this reaction can't be determined (C) In region I and III, the reaction is of first and zero order respectively (D) In region-II, the reaction is of first order (E) In region-II, the order of reaction is in the range of 0.1 to 0.9.

Q98·ChemistrySingle correctJEE Main 2023

An indicator

'X'

is used for studying the effect of variation in concentration of iodide on the rate of reaction of iodide ion with

H_2O_2

at room temp. The indicator

'X'

forms blue colored complex with compound

'A'

present in the solution. The indicator

'X'

and compound

'A'

respectively are:

(A)Methyl orange and $H_2O_2$
(B)Starch and iodide
(C)Starch and $H_2O_2$
(D)Methyl orange and iodine

Q99·ChemistryNumericalJEE Main 2023

A first order reaction has the rate constant,

= 4.6 \times 10^{-3}

s

^{-1}

. The number of correct statement/s from the following is/are Given:

\log 3 = 0.48

A. Reaction completes in 1000 s. B. The reaction has a half-life of 500 s. C. The time required for 10% completion is 25 times the time required for 90% completion. D. The degree of dissociation is equal to

(1 - e^{-kt})

. E. The rate and the rate constant have the same unit.

Q100·ChemistryNumericalJEE Main 2023

For the first order reaction

A \rightarrow B

, the half life is 30 min. The time taken for 75% completion of the reaction is _______ min (nearest integer). (Given:

\log 2=0.3010

,

\log 3=0.4771

,

\log 5=0.6989

)

Q101·ChemistryNumericalJEE Main 2023

The number of correct statement/s from the following is: A. Larger the activation energy, smaller is the value of the rate constant. B. The higher is the activation energy, higher is the value of the temperature coefficient. C. At lower temperatures, increase in temperature causes more change in the value of k than at higher temperature. D. A plot of

\ln k

vs

\tfrac{1}{T}

is a straight line with slope equal to

-\tfrac{E_a}{R}

.

Q102·ChemistrySingle correctJEE Main 2023

A student has studied the decomposition of a gas

AB_3

at

25\,^\circ C

. He obtained the following data.

p

(mmHg):

50

,

100

,

200

,

400

; relative

t_{1/2}

(s):

4

,

2

,

1

,

0.5

. The order of the reaction is

(A) $0$ (zero)
(B) $0.5$
(C) $1$
(D) $2$

Q103·ChemistrySingle correctJEE Advanced 2022

Match the rate expressions in LIST-I for the decomposition of X with the corresponding profiles provided in LIST-II.

\mathrm{X_s}

and k are constants having appropriate units. LIST-I (I) rate

= \frac{k[X]}{X_s + [X]}

under all possible initial concentrations of X (II) rate

= \frac{k[X]}{X_s + [X]}

where initial concentrations of X are much less than

\mathrm{X_s}

(III) rate

= \frac{k[X]}{X_s + [X]}

where initial concentrations of X are much higher than

\mathrm{X_s}

(IV) rate

= \frac{k[X]^{2}}{X_s + [X]}

where initial concentration of X is much higher than

\mathrm{X_s}

(A)I $\rightarrow$ P; II $\rightarrow$ Q; III $\rightarrow$ S; IV $\rightarrow$ T
(B)I $\rightarrow$ R; II $\rightarrow$ S; III $\rightarrow$ S; IV $\rightarrow$ T
(C)I $\rightarrow$ P; II $\rightarrow$ Q; III $\rightarrow$ Q; IV $\rightarrow$ R
(D)I $\rightarrow$ R; II $\rightarrow$ S; III $\rightarrow$ Q; IV $\rightarrow$ R

Q104·ChemistryNumericalJEE Main 2022

Assuming 1

\mu

g of trace radioactive element X with a half life of 30 years is absorbed by a growing tree. The amount of X remaining in the tree after 100 years is___

\times 10^{-1}\mu

g. [Given : ln 10 = 2.303; log2 = 0.30]

Q105·ChemistryNumericalJEE Main 2022

The reaction between X and Y is first order with respect to X and zero order with respect to Y. Examine the data of table and calculate ratio of numerical values of M and L. (Nearest Inetger)

Experiment	[X] mol $L^{-1}$	[Y] mol $L^{-1}$	Initial rate mol $L^{-1}$ $min^{-1}$
I.	0.1	0.1	$2 \times 10^{-3}$
II.	L	0.2	$4 \times 10^{-3}$
III.	0.4	0.4	$M \times 10^{-3}$
IV.	0.1	0.2	$2 \times 10^{-3}$

Q106·ChemistryNumericalJEE Main 2022

For a reaction, given below is the graph of ln k vs

\dfrac{1}{\mathrm{T}}

. The activation energy for the reaction is equal to _____ cal

\mathrm{mol^{-1}}

. (Nearest integer). (Given : R = 2 cal

\mathrm{K^{-1}\,mol^{-1}}

)

Q107·ChemistryNumericalJEE Main 2022

For the given first order reaction A → B the half life of the reaction is 0.3010 min. The ratio of the initial concentration of reactant to the concentration of reactant at time 2.0 min will be equal to __________. (Nearest integer)

Q108·ChemistrySingle correctJEE Main 2022

For kinetic study of the reaction of iodide ion with H

_2

O

_2

at room temperature : (A) Always use freshly prepared starch solution. (B) Always keep the concentration of sodium thiosulphate solution less than that of KI solution. (C) Record the time immediately after the appearance of blue colour. (D) Record the time immediately before the appearance of blue colour. (E) Always keep the concentration of sodium thiosulphate solution more than that of KI solution. Choose the correct answer from the options given below :

(A)(A), (B), (C) only
(B)(A), (D), (E) only
(C)(D), (E) only
(D)(A), (B), (E) only

Q109·ChemistryNumericalJEE Main 2022

2NO + 2

H_{2}

→

N_{2}

+ 2

H_{2}

O The above reaction has been studied at 800°C. The related data are given in the table below The order of the reaction with respect to NO is_____

Reaction serial number	Initial pressure of $H_{2}$ / kPa	Initial Pressure of NO/ kPa	Initial rate $\left(\frac{-dp}{dt}\right)/\left(kPa/s\right)$
1	65.6	40.0	0.135
2	65.6	20.1	0.033
3	38.6	65.6	0.214
4	19.2	65.6	0.106

Q110·ChemistryNumericalJEE Main 2022

[A] → [B] Reactant Product If formation of compound [B] follows the first order of kinetics and after 70 minutes the concentration of [A] was found to be half of its initial concentration. Then the rate constant of the reaction is x × 10

^{-6}

s

^{-1}

. The value of x is______. (Nearest Integer)

Q111·ChemistryNumericalJEE Main 2022

For a reaction A → 2B + C the half lives are 100 s and 50 s when the concentration of reactant A is 0.5 and 1.0 mol L

^{-1}

respectively. The order of the reaction is___ _____. (Nearest Integer)

Q112·ChemistrySingle correctJEE Main 2022

At 30°C, the half life for the decomposition of

AB_{2}

is 200 s and is independent of the initial concentration of

AB_{2}

. The time required for 80% of the

AB_{2}

to decompose is (Given: log 2 = 0.30; log 3 = 0.48)

(A)200 s
(B)323 s
(C)467 s
(D)532 s

Q113·ChemistryNumericalJEE Main 2022

The half life for the decomposition of gaseous compound A is 240 s when the gaseous pressure was 500 Torr initially. When the pressure was 250 Torr, the half life was found to be 4.0 min. The order of the reaction is……. (Nearest integer)

Q114·ChemistryNumericalJEE Main 2022

The activation energy of one of the reactions in a biochemical process is 532611 J

mol^{-1}

. When the temperature falls from 310 K to 300 K, the change in rate constant observed is

k_{300}

= x ×

10^{-3}

k_{310}

. The value of x is _______ . [Given: ln10 = 2.3 R = 8.3 J

K^{-1}

mol^{-1}

]

Q115·ChemistryNumericalJEE Main 2022

The equation k = ( 6.5

\times

10

^{12}

s

^{-1}

) e

^{-26000K/T}

is followed for the decomposition of compound A. The activation energy for the reaction is ____ kJ mol

^{-1}

. [nearest integer] (Given: R = 8.314 J K

^{-1}

mol

^{-1}

)

Q116·ChemistryNumericalJEE Main 2022

A radioactive element has a half life of 200 days. The percentage of original activity remaining after 83 days is ______. (Nearest integer) (Given : antilog 0.125 = 1.333, antilog 0.693 = 4.93)

Q117·ChemistryNumericalJEE Main 2022

For a first order reaction

A \rightarrow B

, the rate constant,

k = 5.5 \times 10^{-14} s^{-1}

. The time required for 67% completion of reaction is x

\times 10^{-1}

times the half life of reaction. The value of x is ________ (Nearest integer) (Given : log 3 = 0.4771)

Q118·ChemistryNumericalJEE Main 2022

The rate constant for a first order reaction is given by the following equation: ln k = 33.24 -

\frac{2.0 \times 10^{4} K}{T}

The Activation energy for the reaction is given by _______ kJ mol

^{-1}

. (In Nearest integer) (Given: R = 8.3 J K

^{-1}

mol

^{-1}

)

Q119·ChemistryNumericalJEE Main 2022

It has been found that for a chemical reaction with rise in temperature by 9K the rate constant gets doubled. Assuming a reaction to be occurring at 300 K, the value of activation energy is found to be ______ kJ mol

^{-1}

. [nearest integer] (Given ln 10 = 2.3, R = 8.3 JK

^{-1}

mol

^{-1}

, log2 = 0.30)

Q120·ChemistryNumericalJEE Main 2022

Catalyst A reduces the activation energy for a reaction by 10 kJ

mol^{-1}

at 300 K. The ratio of rate constants,

\frac{k_{T,Catalysed}}{k_{T,Uncatalysed}}

is

e^x

. The value of x is ________. [nearest integer] [Assume theat the pre-exponential factor is same in both the cases. Given R = 8.31 J

K^{-1}

mol^{-1}

]

Q121·ChemistryNumericalJEE Main 2022

A flask is filled with equal moles of A and B. The half lives of A and B are 100 s and 50 s respectively and are independent of the initial concentration. The time required for the concentration of A to be four times that of B is ______s. (Given : ln 2 = 0.693)

Q122·ChemistryNumericalJEE Main 2022

At 345 K, the half life for the decomposition of a sample of a gaseous compound initially at 55.5 kPa was 340 s. When the pressure was 27.8 kPa, the half life was fund to be 170 s. The order of the reaction is_________. [integer answer]

Q123·ChemistryNumericalJEE Main 2022

For a given chemical reaction

\gamma_1 A + \gamma_2 B \rightarrow \gamma_3 C + \gamma_4 D

Concentration of C changes from 10 mmol

dm^{-3}

to 20 mmol

dm^{-3}

in 10 seconds. Rate of appearance of D is 1.5 times the rate of disappearance of B which is twice the rate of disappearance A. The rate of appearance of D has been experimentally determined to be 9 mmol

dm^{-3}

s^{-1}

. Therefore the rate of reaction is ________mmol

dm^{-3}

s^{-1}

. (Nearest Integer)

Q124·ChemistryNumericalJEE Main 2022

The rate constants for decomposition of acetaldehyde have been measured over the temperature range 700–1000 K. The data has been analysed by plotting In k vs

\dfrac{10^{3}}{T}

graph. The value of activation energy for the reaction is ____ kJ mol

^{-1}

. (Nearest integer) (Given : R = 8.31 J K

^{-1}

mol

^{-1}

)

Q125·ChemistrySingle correctJEE Main 2022

For a first order reaction, the time required for completion of 90% reaction is 'x' times the half life of the reaction. The value of 'x' is (Given: ln 10 = 2.303 and log 2 = 0.3010)

(A)1.12
(B)2.43
(C)3.32
(D)33.31

Q126·ChemistryMultiple correctJEE Advanced 2021

For the following reaction

2\mathbf{X} + \mathbf{Y} \xrightarrow{k} \mathbf{P}

the rate of reaction is

\frac{d[\mathbf{P}]}{dt} = k[\mathbf{X}]

. Two moles of

\mathbf{X}

are mixed with one mole of

\mathbf{Y}

to make 1.0 L of solution. At 50 s, 0.5 mole of

\mathbf{Y}

is left in the reaction mixture. The correct statement(s) about the reaction is(are) (Use: ln 2 = 0.693)

(A)The rate constant, $k$ , of the reaction is $13.86 \times 10^{-4}$ s $^{-1}$ .
(B)Half–life of $\mathbf{X}$ is 50s.
(C)At 50 s, $-\frac{d[\mathbf{X}]}{dt} = 13.86 \times 10^{-3}$ mol L $^{-1}$ s $^{-1}$ .
(D)At 100 s, $-\frac{d[\mathbf{Y}]}{dt} = 3.46 \times 10^{-3}$ mol L $^{-1}$ s $^{-1}$ .

Q127·ChemistrySingle correctJEE Main 2021

Which one of the following given graphs represents the variation of rate constant (k) with temperature (T) for an endothermic reaction ?

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q128·ChemistryNumericalJEE Main 2021

For a first order reaction, the ratio of the time for 75% completion of a reaction to the time for 50% completion is ___. (Integer answer)

Q129·ChemistryNumericalJEE Main 2021

For the reaction A

\rightarrow

B, the rate constant k(in s

^{-1}

) is given by

\log_{10} \mathrm{k} = 20.35 - \frac{(2.47 \times 10^{3})}{\mathrm{T}}

The energy of activation in kJ mol

^{-1}

is ________. (Nearest integer) [Given : R = 8.314 J K

^{-1}

mol

^{-1}

]

Q130·ChemistryNumericalJEE Main 2021

The first order rate constant for the decomposition of CaCO

_{3}

at 700 K is 6.36 × 10

^{-3}

s

^{-1}

and activation energy is 209 kJ mol

^{-1}

. Its rate constant (in s

^{-1}

) at 600 K is x × 10

^{-6}

. The value of x is _____ . (Nearest integer) [Given R = 8.31 J K

^{-1}

mol

^{-1}

; log 6.36 × 10

^{-3}

= −2.19, 10

^{-4.79}

= 1.62 × 10

^{-5}

]

Q131·ChemistryNumericalJEE Main 2021

The reaction that occurs in a breath analyser, a device used to determine the alcohol level in a person's blood stream is

2K_2Cr_2O_7 + 8H_2SO_4 + 3C_2H_6O \rightarrow 2Cr_2(SO_4)_3 + 3C_2H_4O_2 + 2K_2SO_4 + 11H_2O

If the rate of appearance of

Cr_2(SO_4)_3

is 2.67 mol

min^{-1}

at a particular time, the rate of disappearance of

C_2H_6O

at the same time is ________ mol

min^{-1}

. (Nearest integer)

Q132·ChemistryNumericalJEE Main 2021

The following data was obtained for chemical reaction given below at 975 K.

2NO_{(g)} + 2H_{2(g)} \rightarrow N_{2(g)} + 2H_2O_{(g)}

[NO]

(mol

L^{-1}

),

[H_2]

(mol

L^{-1}

), Rate (mol

L^{-1}s^{-1}

) (A)

8 \times 10^{-5}

,

8 \times 10^{-5}

,

7 \times 10^{-9}

(B)

24 \times 10^{-5}

,

8 \times 10^{-5}

,

2.1 \times 10^{-8}

(C)

24 \times 10^{-5}

,

32 \times 10^{-5}

,

8.4 \times 10^{-8}

The order of the reaction with respect to NO is ________. [Integer answer]

Q133·ChemistryNumericalJEE Main 2021

The reaction rate for the reaction

[\mathrm{PtCl_4}]^{2-} + \mathrm{H_2O} \rightleftharpoons [\mathrm{Pt(H_2O)Cl_3}]^{-} + \mathrm{Cl}^{-}

was measured as a function of concentrations of different species. It was observed that

\frac{-d\left[[\mathrm{PtCl_4}]^{2-}\right]}{dt} = 4.8 \times 10^{-5} \left[[\mathrm{PtCl_4}]^{2-}\right] - 2.4 \times 10^{-3} \left[[\mathrm{Pt(H_2O)Cl_3}]^{-}\right]\left[\mathrm{Cl}^{-}\right]

. where square brackets are used to denote molar concentrations. The equilibrium constant

K_c =

______. (Nearest integer)

Q134·ChemistrySingle correctJEE Main 2021

For a reaction of order n, the unit of the rate constant is:

(A) $mol^{1-n} L^{n-1} s^{-1}$
(B) $mol^{1-n} L^{1-n} s^{-1}$
(C) $mol^{1-n} L^{2n} s^{-1}$
(D) $mol^{1-n} L^{1-n} s$

Q135·ChemistryNumericalJEE Main 2021

For a chemical reaction A→B, it was found that concentration of B is increased by 0.2 mol L

^{-1}

in 30 min. The average rate of the reaction is __________

\times10^{-1}

mol L

^{-1}

h

^{-1}

. (in nearest integer)

Q136·ChemistrySingle correctJEE Main 2021

For the following graphs, Choose from the options given below, the correct one regarding order of reaction is:

(A)(a) and (b) zero order (e) First order
(B)(b) and (d) zero order (e) First order
(C)(a) and (b) zero order (c) and (e) First order
(D)(b) zero order (c) and (e) First order

Q137·ChemistryNumericalJEE Main 2021

\mathrm{N_2O_{5(g)} \rightarrow 2NO_{2(g)} + \frac{1}{2}O_{2(g)}}

In the above first order reaction the initial concentration of

\mathrm{N_2O_5}

is

2.40 \times 10^{-2}

mol L

^{-1}

at 318K. The concentration of

\mathrm{N_2O_5}

after 1 hours was

1.60 \times 10^{-2}

mol L

^{-1}

. The rate constant of the reaction at 318K is _________

\times 10^{-3}

min

^{-1}

. ( Nearest integer ) [Given : log3 = 0.477, log5 = 0.699 ]

Q138·ChemistryNumericalJEE Main 2021

The inactivation rate of a viral preparation in proportional to the amount of virus. In the first minute after preparation, 10% of the virus is inactivated. The rate constant for viral inactivation is ______________

\times 10^{-3}

min

^{-1}

. (Nearest integer) [ Use:

\ell n10

= 2.303; log

_{10}

3=0.477; property of logarithm:

\log x^y = y \log x

]

Q139·ChemistryNumericalJEE Main 2021

\mathrm{PCl_5}\left(\mathrm{g}\right) \rightarrow \mathrm{PCl_3}\left(\mathrm{g}\right) + \mathrm{Cl_2}\left(\mathrm{g}\right)

In the above first order reaction, the concentration of

\mathrm{PCl_5}

reduces from initial concentration

50\ \mathrm{mol\ L^{-1}}

to

10\ \mathrm{mol\ L^{-1}}

in 120 minutes at 300 K. The rate constant for the reaction at 300 K is

x \times 10^{-2}\ \mathrm{min^{-1}}

. the value of

x

is ________. [Given

\log 5 = 0.6989

]

Q140·ChemistryNumericalJEE Main 2021

2 NO(g) + Cl

_{2}

(g) ⇌ 2 NOCl(s) This reaction was studied at −10°C and the following data was obtained run [NO]

_{0}

[Cl

_{2}

]

_{0}

r

_{0}

1 0.10 0.10 0.18 2 0.10 0.20 0.35 3 0.20 0.20 1.40 [NO]

_{0}

and [Cl

_{2}

]

_{0}

are the initial concentrations and r

_{0}

is the initial reaction rate. The overall order of the reaction is ______. (Round off to the Nearest Integer).

Q141·ChemistryNumericalJEE Main 2021

A reaction has a half life of 1 min. The time required for 99.9% completion of the reaction is ______ min. (Round off to the Nearest integer) [Use : ln 2= 0.69, ln 10 = 2.3]

Q142·ChemistryNumericalJEE Main 2021

For a certain first order reaction 32% of the reactant is left after 570 s. The rate constant of this reaction is ________

\times 10^{-3}\ \mathrm{s^{-1}}

. (Round off to the Nearest Integer). [Given :

\log_{10} 2 = 0.301

,

\ln 10 = 2.303

]

Q143·ChemistryNumericalJEE Main 2021

The reaction 2A + B

_{2}

\rightarrow

2AB is an elementary reaction. For a certain quantity of reactants, if the volume of the reaction vessel is reduced by a factor of 3, the rate of the reaction increases by a factor of ____. (Round off to the Nearest Integer).

Q144·ChemistryNumericalJEE Main 2021

The decomposition of formic acid on gold surface follows first order kinetics. If the rate constant at 300 K is 1.0 × 10

^{-3}

s

^{-1}

and the activation energy E

_{a}

= 11.488 kJ mol

^{-1}

, the rate constant at 200 K is _______ × 10

^{-5}

s

^{-1}

. (Round of to the Nearest Integer). (Given : R = 8.314 J mol

^{-1}

K

^{-1}

)

Q145·ChemistryNumericalJEE Main 2021

A and B decompose via first order kinetics with half-lives 54.0 min and 18.0 min respectively. Starting from an equimolar non reactive mixture of A and B, the time taken for the concentration of A to become 16 times that of B is ______ min. (Round off to the Nearest Integer).

Q146·ChemistryNumericalJEE Main 2021

If the activation energy of a reaction is 80.9 kJ

mol^{-1}

, the fraction of molecules at 700K, having enough energy to react to form products is

e^{-x}

. The value of x is _______. (Rounded off to the nearest integer) [Use R = 8.31

JK^{-1}

mol^{-1}

]

Q147·ChemistryNumericalJEE Main 2021

An exothermic reaction X → Y has an activation energy 30 kJ mol

^{-1}

. If energy change ΔE during the reaction is −20 kJ, then the activation energy for the reverse reaction in kJ is _______.

Q148·ChemistryNumericalJEE Main 2021

For the reaction, aA + bB → cC + dD, the plot of log k vs

\frac{1}{T}

is given below: The temperature at which the rate constant of the reaction is 10

^{-4}

s

^{-1}

is _______ K. [Rounded off to the nearest integer) [Given: The rate constant of the reaction is 10

^{-5}

s

^{-1}

at 500 K]

Q149·ChemistryNumericalJEE Main 2021

The rate constant of a reaction increases by five times on increase in temperature from 27

^{0}

C to 52

^{0}

C. The value of activation energy in kJ mol

^{-1}

is ______. (Rounded off to the nearest integer) [R=8.314 J K

^{-1}

mol

^{-1}

]

Q150·ChemistryNumericalJEE Main 2021

Sucrose hydrolyses in acid solution into glucose and fructose following first order rate law with a half-life of 3.33 h at 25ºC. After 9h, the fraction of sucrose remaining is f. The value of

\log_{10}\left(\frac{1}{f}\right)

is ___________×

10^{-2}

(Rounded off to the nearest integer) [Assume: ln10 = 2.303, ln2 = 0.693]

Q151·ChemistryNumericalJEE Main 2021

Gaseous cyclobutene isomerizes to butadiene in a first order process which has a 'k' value of

3.3 \times 10^{-4}\,\mathrm{s^{-1}}

at 153°C. The time in minutes it takes for the isomerization to proceed 40% to completion at this temperature is ________. (Rounded off to the nearest integer)

Q152·ChemistryNumericalJEE Advanced 2020

^{238}_{92}U

is known to undergo radioactive decay to form

^{206}_{82}Pb

by emitting alpha and beta particles. A rock initially contained

68 \times 10^{-6}

g of

^{238}_{92}U

. If the number of alpha particles that it would emit during its radioactive decay of

^{238}_{92}U

to

^{206}_{82}Pb

in three half-lives is

Z \times 10^{18}

, then what is the value of Z ?

Q153·ChemistryMultiple correctJEE Advanced 2020

Which of the following plots is(are) correct for the given reaction? (

[P]_{0}

is the initial concentration of P)

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q154·ChemistrySingle correctJEE Main 2020

Consider the following reactions

A \rightarrow P1; B \rightarrow P2; C \rightarrow P3; D \rightarrow P4

, The order of the above reactions are a, b, c and d, respectively. The following graph is obtained when log[rate] vs. log[conc.] are plotted: Among the following, the correct sequence for the order of the reactions is:

(A)d > a > b > c
(B)a > b > c > d
(C)c > a > b > d
(D)d > b > a > c

Q155·ChemistrySingle correctJEE Main 2020

The rate constant (k) of a reaction is measured at different temperatures (T), and the data are plotted in the given figure. The activation energy of the reaction in kJ mol

^{-1}

is: (R is gas constant)

(A)2R
(B)2/R
(C)R
(D)1/R

Q156·ChemistrySingle correctJEE Main 2020

A flask contains a mixture of compounds A and B. Both compounds decompose by first – order kinetics. The half lives for A and B are 300 s and 180 s, respectively. If the concentrations of A and B are equal initially, the line required for the concentration of A to be four times that of B (in s) is : (Use

\ln 2 = 0.693

)

(A)120
(B)300
(C)900
(D)180

Q157·ChemistryNumericalJEE Main 2020

If 75% of a first order reaction was completed in 90 minutes, 60% of the same reaction would be completed in approximately (in minutes) __________. (Take: log 2 = 0.30; log 2.5 = 0.40)

Q158·ChemistrySingle correctJEE Main 2020

It is true that:

(A)A first order reaction is always a single step reaction.
(B)A zero order reaction is a single step reaction.
(C)A second order reaction is always a multistep reaction.
(D)A zero order reaction is a multistep reaction.

Q159·ChemistrySingle correctJEE Main 2020

For the reaction

2A + 3B + \frac{3}{2}C \rightarrow 3P

, which statement is correct?

(A) $\frac{dn_{A}}{dt} = \frac{2}{3}\frac{dn_{B}}{dt} = \frac{3}{4}\frac{dn_{C}}{dt}$
(B) $\frac{dn_{A}}{dt} = \frac{dn_{B}}{dt} = \frac{dn_{C}}{dt}$
(C) $\frac{dn_{A}}{dt} = \frac{3}{2}\frac{dn_{B}}{dt} = \frac{3}{4}\frac{dn_{C}}{dt}$
(D) $\frac{dn_{A}}{dt} = \frac{2}{3}\frac{dn_{B}}{dt} = \frac{4}{3}\frac{dn_{C}}{dt}$

Q160·ChemistrySingle correctJEE Main 2020

For following reactions A

\xrightarrow{700\ K}

Product A

\xrightarrow[\text{catalyst}]{500\ K}

Product it was found that the E

_a

is decreased by 30 kJ/mol in the presence of catalyst. If the rate remains unchanged, the activation energy for catalysed reaction is (Assume pre exponential factor is same):

(A)135 kJ/mol
(B)105 kJ/mol
(C)75 kJ/mol
(D)198 kJ/mol

Q161·ChemistrySingle correctJEE Main 2020

The rate of a certain biochemical reaction at physiological temperature (T) occurs 10

^{6}

times faster with enzyme than without. The change in the activation energy upon adding enzyme is :

(A)− 6 (2.303)RT
(B)+ 6RT
(C)− 6RT
(D)+ 6(2.303)RT

Q162·ChemistrySingle correctJEE Main 2020

Consider the following plots of rate constant versus

\dfrac{1}{T}

for four different reactions. Which of the following order is correct for the activation energies of these reactions?

(A)E $_c$ > E $_a$ > E $_d$ > E $_b$
(B)E $_b$ > E $_d$ > E $_c$ > E $_a$
(C)E $_a$ > E $_c$ > E $_d$ > E $_b$
(D)E $_b$ > E $_a$ > E $_d$ > E $_c$

Q163·ChemistryNumericalJEE Main 2020

During the nuclear explosion, one of the product of

^{90}

Sr with half life of 6.93 years. If 1

\mu

g of

^{90}

Sr absorbed in the bones of newly born baby in place of Ca, how much time, in years is required to reduce it by 90% if it is not lost metabolically

Q164·ChemistrySingle correctJEE Main 2020

For the reaction

2H_2(g) + 2NO(g) \longrightarrow N_2(g) + 2H_2O

, the observed rate expression is, rate =

k_f[NO]^2[H_2]

. The rate expression for the reverse reaction is:

(A) $k_b[N_2][H_2O]$
(B) $k_b[N_2][H_2O]^2/[NO]$
(C) $k_b[N_2][H_2O]^2/[H_2]$
(D) $k_b[N_2][H_2O]^2$

Q165·ChemistryNumericalJEE Advanced 2019

Experiment No. | [A] (mol dm

^{-3}

) | [B] (mol dm

^{-3}

) | [C] (mol dm

^{-3}

) | Rate of reaction (mol dm

^{-3}

s

^{-1}

) 1 | 0.2 | 0.1 | 0.1 | 6.0

\times

10

^{-5}

2 | 0.2 | 0.2 | 0.1 | 6.0

\times

10

^{-5}

3 | 0.2 | 0.1 | 0.2 | 1.2

\times

10

^{-4}

4 | 0.3 | 0.1 | 0.1 | 9.0

\times

10

^{-5}

The rate of the reaction for [A] = 0.15 mol dm

^{-3}

, [B] = 0.25 mol dm

^{-3}

and [C] = 0.15 mol dm

^{-3}

is found to be Y

\times

10

^{-5}

mol dm

^{-3}

s

^{-1}

. The value of Y is ……… .

Q166·ChemistryNumericalJEE Advanced 2019

The decomposition reaction

2\mathrm{N}_{2}\mathrm{O}_{5}\left(g\right) \xrightarrow{\Delta} 2\mathrm{N}_{2}\mathrm{O}_{4}\left(g\right) + \mathrm{O}_{2}\left(g\right)

is started in a closed cylinder under isothermal isochoric condition at an initial pressure of 1 atm. After Y

\times

10

^{3}

s, the pressure inside the cylinder is found to be 1.45 atm. If the rate constant of the reaction is 5

\times

10

^{-4}

s

^{-1}

, assuming ideal gas behaviour, the value of \textbf{Y} is________

Q167·ChemistrySingle correctJEE Main 2019

NO

_{2}

required for a reaction is produced by the decomposition of N

_{2}

O

_{5}

in CCl

_{4}

as per the equation

2N_{2}O_{5}(g) \rightarrow 4NO_{2}(g) + O_{2}(g)

The initial concentration of N

_{2}

O

_{5}

is 3.00 mol L

^{-1}

and it is 2.75 mol L

^{-1}

after 30 minutes. The rate of formation of NO

_{2}

is :

(A)1.667 $\times$ 10 $^{-2}$ mol L $^{-1}$ min $^{-1}$
(B)4.167 $\times$ 10 $^{-3}$ mol L $^{-1}$ min $^{-1}$
(C)8.333 $\times$ 10 $^{-3}$ mol L $^{-1}$ min $^{-1}$
(D)2.083 $\times$ 10 $^{-3}$ mol L $^{-1}$ min $^{-1}$

Q168·ChemistrySingle correctJEE Main 2019

In the following reaction; xA

\longrightarrow

yB

\log_{10}\left[-\dfrac{d[A]}{dt}\right]=\log_{10}\left[\dfrac{d[B]}{dt}\right]+0.3010

'A' and 'B' respectively can be :

(A)C $_2$ H $_2$ and C $_6$ H $_6$
(B)n-Butane and Iso-butane
(C)N $_2$ O $_4$ and NO $_2$
(D)C $_2$ H $_4$ and C $_4$ H $_8$

Q169·ChemistrySingle correctJEE Main 2019

A bacterial infection in an internal would grows as N'(t) = N

_0

exp(t), where the time t is in hours. A dose of antibiotic, taken orally, needs 1 hour to reach the wound. Once it reaches there, the bacterial population goes down as

\frac{dN}{dt} = -5N^2

. What will be the plot of

\frac{N_0}{N}

vs, t after 1 hour?

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q170·ChemistrySingle correctJEE Main 2019

For the re action of H

_2

w i t h I

_2

, the rate constant is

2.5 \times 10^{-4}

dm

^3

mol

^{-1}

s

^{-1}

at 327°C and 1.0 dm

^3

mol

^{-1}

s

^{-1}

at 527°C. The activation energy for the reaction, in kJ mol

^{-1}

is: (R = 8.314 J K

^{-1}

mol

^{-1}

)

(A)72
(B)166
(C)150
(D)59

Q171·ChemistrySingle correctJEE Main 2019

The given plots represent the variation of the concentration of a reactant R with time for two different reactions (i) and (ii). The respective orders of the reactions are:

(A)1, 1
(B)0, 2
(C)0, 1
(D)1, 0

Q172·ChemistrySingle correctJEE Main 2019

Consider the given plot of enthalpy of the following reaction between A and B. A + B

\rightarrow

C + D Identify the incorrect statement

(A)C is the thermodynamically stable product
(B)Formation of A and B from C has highest enthalpy of activation
(C)D is kinetically stable product
(D)Activation enthalpy to form C is 5kJ mol $^{-1}$ less than that to form D

Q173·ChemistrySingle correctJEE Main 2019

For a reaction scheme.

A\xrightarrow{k_{1}}B\xrightarrow{k_{2}}C

if the rate of formation of B is set to be zero then the concentration of B is given by

(A) $\left(\dfrac{k_{1}}{k_{2}}\right)[A]$
(B) $(k_{1}-k_{2})[A]$
(C) $k_{1}k_{2}[A]$
(D) $(k_{1}+k_{2})[A]$

Q174·ChemistrySingle correctJEE Main 2019

For the reaction

2A + B \rightarrow C

, the values of initial rate at different reactant concentrations are given in the table below: The rate law for the reaction is:

[A] (mol L $^{-1}$ )	[B] (mol L $^{-1}$ )	Initial Rate (mol L $^{-1}$ s $^{-1}$ )
0.05	0.05	0.045
0.10	0.05	0.090
0.20	0.10	0.72

(A)Rate = $k[A]^2[B]^2$
(B)Rate = $k[A][B]^2$
(C)Rate = $k[A][B]$
(D)Rate = $k[A]^2[B]$

Q175·ChemistrySingle correctJEE Main 2019

Decomposition of X exhibits a rate constant for 0.05

\mu g

/year. How many years are required for the decomposition of 5

\mu g

of X into 2.5

\mu g

?

(A)50
(B)25
(C)20
(D)40

Q176·ChemistrySingle correctJEE Main 2019

For a certain reaction consider the plot of ℓnk versus 1/T given in the figure. If the rate constant of this reaction at 400 K is

10^{-5}

s

^{-1}

, then the rate constant at 500 K is:

(A) $10^{-6}$ s $^{-1}$
(B) $2\times10^{-4}$ s $^{-1}$
(C) $10^{-4}$ s $^{-1}$
(D) $4\times10^{-4}$ s $^{-1}$

Q177·ChemistrySingle correctJEE Main 2019

The reaction 2X

\rightarrow

B is a zeroth order reaction. If the initial concentration of X is 0.2M, the half life is 6 h. When the initial concentration of X is 0.5 M, the time required to reach its final concentration of 0.2 M will be:

(A)9.0 h
(B)12.0 h
(C)18.0 h
(D)7.2 h

Q178·ChemistrySingle correctJEE Main 2019

If a reaction follows the Arrhenius equation, the plot ln k v

1/(RT)

gives straight line with a gradient

(-y)

unit. The energy required to activate the reactant is:

(A)y/R unit
(B)y unit
(C)yR unit
(D)–y unit

Q179·ChemistrySingle correctJEE Main 2019

Consider the given plots for a reaction obeying Arrhenius equation (0°C < T < 300°C) : (k and E

_{a}

are rate constant and activation energy respectively) Choose the correct option:

(A)I is right but II is wrong
(B)Both I and Ii are correct
(C)I is wrong but II is right
(D)Both I and II are wrong

Q180·ChemistrySingle correctJEE Main 2019

For the reaction,

2A + B \longrightarrow

products, when the concentrations of A and B both were doubled, the rate of the reaction increased from 0.3 mol L

^{-1}

s

^{-1}

to 2.4 mol L

^{-1}

s

^{-1}

. When the concentration of A alone is doubled, the rate increased from 0.3 mol L

^{-1}

s

^{-1}

to 0.6 mol L

^{-1}

s

^{-1}

. Which one of the following statements is correct?

(A)Total order of the reaction is 4
(B)Order of the reaction with respect to B is 2
(C)Order of the reaction with respect to B is 1
(D)Order of the reaction with respect to A is 2

Q181·ChemistrySingle correctJEE Main 2019

The following results were obtained during kinetic studies of the reaction 2A + B

\longrightarrow

products. The time (in minutes) required to consume half of A is

Experiment	[A] (in mol L $^{-1}$ )	[B] (in mol L $^{-1}$ )	Initial rate of reaction (in mol L $^{-1}$ min $^{-1}$ )
I	0.10	0.20	6.93 $\times$ 10 $^{-3}$
II	0.10	0.25	6.93 $\times$ 10 $^{-3}$
III	0.20	0.30	1.386 $\times$ 10 $^{-2}$

(A)5
(B)10
(C)1
(D)100

Q182·ChemistryNumericalJEE Advanced 2018

Consider the following reversible reaction,

A(g) + B(g) \rightleftharpoons AB(g)

The activation energy of the backward reaction exceeds that of the forward reaction by 2RT (in J

mol^{-1}

). If the pre-exponential factor of the forward reaction is 4 times that of the reverse reaction, the absolute value of

\Delta G^{\ominus}

(in J

mol^{-1}

) for the reaction at 300 K is ____. (Given;

\ln(2) = 0.7

, RT = 2500 J

mol^{-1}

at 300 K and

G

is the Gibbs energy)

Q183·ChemistryMultiple correctJEE Advanced 2018

For a first order reaction

A(g) \rightarrow 2B(g) + C(g)

at constant volume and 300 K, the total pressure at the beginning (t = 0) and at time t are

P_{0}

and

P_{t}

, respectively. Initially, only A is present with concentration

[A]_{0}

, and

t_{1/3}

is the time required for the partial pressure of A to reach

1/3^{rd}

of its initial value. The correct option(s) is (are) (Assume that all these gases behave as ideal gases)

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q184·ChemistryMultiple correctJEE Advanced 2017

In a bimolecular reaction, the steric factor P was experimentally determined to be 4.5. The correct option(s) among the following is(are)

(A)The activation energy of the reaction is unaffected by the value of the steric factor
(B)Experimentally determined value of frequency factor is higher than that predicted by Arrhenius equation
(C)Since P = 4.5, the reaction will not proceed unless an effective catalyst is used
(D)The value of frequency factor predicted by Arrhenius equation is higher than that determined experimentally

Q185·ChemistryMultiple correctJEE Advanced 2016

According to the Arrhenius equation,

(A)a high activation energy usually implies a fast reaction.
(B)rate constant increases with increase in temperature. This is due to a greater number of collisions whose energy exceeds the activation energy.
(C)higher the magnitude of activation energy, stronger is the temperature dependence of the rate constant.
(D)the pre-exponential factor is a measure of the rate at which collisions occur, irrespective of their energy.

Q186·ChemistryIntegerJEE Advanced 2015

In dilute aqueous

\mathrm{H_{2}SO_{4}}

, the complex diaquodioxalatoferrate(II) is oxidized by

\mathrm{MnO_{4}^{-}}

. For this reaction, the ratio of the rate of change of

[\mathrm{H^{+}}]

to the rate of change of

[\mathrm{MnO_{4}^{-}}]

is

Q187·ChemistrySingle correctJEE Advanced 2014

For the elementary reaction

\mathbf{M} \rightarrow \mathbf{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 is

(A)4
(B)3
(C)2
(D)1

Q188·ChemistrySingle correctJEE Advanced 2013

In the reaction, P + Q → R + S the time taken for 75% reaction of P is twice the time taken for 50% reaction of P. The concentration of Q varies with reaction time as shown in the figure. The overall order of the reaction is

(A)2
(B)3
(C)0
(D)1

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