List of top Chemistry Questions on Chemical Kinetics

During Kinetic study of reaction 2A + B \(\mapsto \) C + D, the following results were obtained:

	A[M]	B[M]	initial rate of formation of D
I	0.1	0.1	6.0 × 10-3
II	0.3	0.2	7.2 × 10-2
III	0.3	0.4	2.88 × 10-1
IV	0.4	0.1	2.40 × 10-2

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

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)

Consider the following first-order gas phase reaction at constant temperature \[ \text{A(g)} \rightarrow 2\text{B(g)} + \text{C(g)} \] If the total pressure of the gases is found to be 200 torr after 23 sec. and 300 torr upon the complete decomposition of \( \text{A} \) after a very long time, then the rate constant of the given reaction is \( \dots \dots \times 10^{-2} \, \text{s}^{-1} \) (nearest integer). \[ \text{[Given: } \log_{10}(2) = 0.301 \text{]} \]

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

$\text{NO}_2 \text{ required for a reaction is produced by decomposition of } \text{N}_2\text{O}_5 \text{ in } \text{CCl}_4 \text{ as by equation}$
\[ 2\text{N}_2\text{O}_{5(g)} \rightarrow 4\text{NO}_{2(g)} + \text{O}_{2(g)} \]
$\text{The initial concentration of } \text{N}_2\text{O}_5 \text{ is } 3 \text{ mol L}^{-1} \text{ and it is } 2.75 \text{ mol L}^{-1} \text{ after 30 minutes.}$
$\text{The rate of formation of } \text{NO}_2 \text{ is } x \times 10^{-3} \text{ mol L}^{-1} \text{ min}^{-1} , \text{ value of } x \text{ is \_\_\_\_\_\_.}$

Consider the following transformation involving first-order elementary reaction in each step at constant temperature as shown below: \[ \text{A} + \text{B} \xrightarrow{\text{Step 1}} \text{C} \xrightarrow{\text{Step 2}} \text{P}\] Some details of the above reaction are listed below:

If the overall rate constant of the above transformation (\(k\)) is given as \(k = \frac{k_1 k_2}{k_3}\) and the overall activation energy (\(E_a\)) is \(400 \, \text{kJ mol}^{-1}\), then the value of \(E_{a3}\) is ______ \( \text{kJ mol}^{-1} \) (nearest integer).

$\text{Time required for completion of 99.9\% of a first order reaction is \_\_\_\_\_\_ times of half life } (t_{1/2}) \text{ of the reaction.}$

For a reaction taking place in three steps at the same temperature, the overall rate constant \( K = \frac{K_1 K_2}{K_3} \). If \( E_{a1} \), \( E_{a2} \), and \( E_{a3} \) are 40, 50, and 60 kJ/mol respectively, the overall \( E_a \) is ____ kJ/mol.

For a reaction taking place in three steps at the same temperature, the overall rate constant \( K = \frac{K_1 K_2}{K_3} \). If \( E_{a1} \), \( E_{a2} \), and \( E_{a3} \) are 40, 50, and 60 kJ/mol respectively, the overall \( E_a \) is ____ kJ/mol.

The rate of a first order reaction is \( 0.04 \, \text{mol} \, \text{L}^{-1} \, \text{s}^{-1} \) at 10 minutes and \( 0.03 \, \text{mol} \, \text{L}^{-1} \, \text{s}^{-1} \) at 20 minutes after initiation. Half-life of the reaction is \( \_\_\_\_ \) minutes. (Given \( \log 2 = 0.3010, \, \log 3 = 0.4771 \))

The data provided in the table were obtained from the following reaction, carried out at 273 𝐾.
𝐴 + 𝐵 → 𝐶 

Initial concentration of [𝐴] 𝑚𝑜𝑙 $𝐿 ^{−1}$	Initial concentration of [𝐵] 𝑚𝑜𝑙$𝐿 ^{−1}$	Initial rate of formation of [𝐶] 𝑚𝑜𝑙 $𝐿^{−1} 𝑠 ^{−1}$
0.2	0.2	0.3
0.4	0.2	0.6
0.4	0.4	2.4

The order of the reaction with respect to 𝐴 is _________.

Consider the following reaction,
\(2H_2(g) + 2NO(g) \rightarrow N_2(g) + 2H_2O(g)\)
which follows the mechanism given below:
\(2NO(g)\underset{k_{-1}}{\stackrel{k_1}{\rightleftharpoons}} N_2O_2(g)\) (fast equilibrium)
\(N_2O_2(g)+H_2(g) \xrightarrow[]{K_2}N_2O(g)+H_2O\)  (slow reaction)
\(N_2O(g)+H_2(g) \xrightarrow[]{K_3}N_2(g)+H_2O\)  (fast reaction)
The order of the reaction is________

For a certain reaction, the rate=\(k[A]^2[B]\) when the initial concentration of A is tripled keeping concentration of B constant, the initial rate would

A student has studied the decomposition of a gas AB₃​ at 25^∘C. He obtained the following data.

The order of the reaction is……….

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 is ______ s. (Nearest integer)
(Given: \(\ln 10=2.3 ; \log 2=0.3\))

'$A$' in the given reaction is

How many statements are correct:

1. If there is no relation between rate constant and temperature, then activation energy is negative.
2. If the activation energy is zero, rate constant is temperature independent.
3. If rate constant increases with increase of temperature, activation energy is positive.
4. If rate constant decreases with increase in temperature, activation energy is negative.

Select the correct option:
\(2CO (g) + O_2 (g) → 2CO_2 (g) ; ΔH = -x KJ/mol\)
\(C (graphite) + O_2(g) → CO_2 (g) ; AH = -y KJ/mol\)
Then AH for, \(C(graphite) + \frac{1}{2} O_2 (g) → CO (g):\)

Which of the following conformations will be the most stable?

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 : $\log _g 2=03010$ $ \log 3=04771 $ $ \log 5=06989$

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 $\frac{1}{T}$ is a straight line with slope equal to $-\frac{E_a}{R}$

A first order reaction has the rate constant, $k =46 \times 10^{-3} s ^{-1}$ 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 $\left(1-e^{-k t}\right)$ 
E. The rate and the rate constant have the same unit

If compound A reacts with $B$ following first order kinetics with rate constant $2.011 \times 10^{-3} s ^{-1}$ The time taken by $A$ (in seconds) to reduce from $7\, g$ to $2\, g$ will be ______ (Nearest Integer) $[\log 5=0.698, \log 7=0.845, \log 2=0.301]$