Write two differences between order of reaction and molecularity of reaction.
CBSE CLASS 12 • CHEMISTRY • CHAPTER 03
Chemical Kinetics
194 distinct questions across 249 board paper set appearances (2022–2026).
Assertion (A) : For a zero order reaction, the unit of rate constant and rate of reaction are same.
Reason (R) : Rate of reaction for zero order reaction is independent of concentration of reactant.
Identify the correct statement :
(A) Molecularity of a reaction is an experimental quantity.
(B) For complex reactions molecularity has no meaning.
(C) Molecularity of a reaction can be zero or even a fraction.
(D) Molecularity more than three is very common in chemical reactions.
Assertion (A) : The molecularity of the given reaction is $2$
$2\text{HI} \longrightarrow \text{H}_2 + \text{I}_2$
Reason (R) : Two molecules of the reactants are involved in simultaneous collision between them.
(A) The concentration of the reactant is reduced from $0.6 \text{ mol L}^{-1}$ to $0.2 \text{ mol L}^{-1}$ in $5$ minutes in a first order reaction. Calculate rate constant of the reaction. $(\log 3 = 0.48)$
OR
(B) Rate constant $k$ for the first order reaction is $2.54 \times 10^{-3} \text{ s}^{-...
(a) Reactions of which order will show the rate to be independent of the concentration of the reactant ? Give one example of this order.
(b) State the condition under which a bimolecular reaction may be kinetically a first order reaction.
Half-life ($t_{1/2}$) of a first order reaction is $1386 \text{ s}$. The value of rate constant is :
(A) $0.5 \times 10^4 \text{ s}^{-1}$
(B) $5.0 \times 10^{-4} \text{ s}^{-1}$
(C) $0.5 \times 10^{-5} \text{ s}^{-1}$
(D) $0.5 \times 10^{-2} \text{ s}^{-1}$
(a) (i) A first order reaction is $20%$ complete in $10$ minutes. Calculate the time taken when $80%$ of the reaction will be completed.
[Given : $\log 5 = 0\cdot7$, $\log 4 = 0\cdot6$]
(ii) For a chemical reaction $\text{R} \rightarrow \text{P}$, variation in $\ln[\text{R}]$ vs. time (t) graph is g...
(a) (i) The initial concentration of $\text{N}_2\text{O}_5$ in the first order reaction :
$$\text{N}_2\text{O}_5\text{ (g)} \rightarrow 2\text{NO}_2\text{ (g)} + \frac{1}{2}\text{O}_2\text{ (g)}$$
was $1\cdot2 \times 10^{-2}\text{ mol L}^{-1}$. The concentration of $\text{N}_2\text{O}_5$ after $60$ ...
The role of a catalyst is to change :
(A) equilibrium constant
(B) enthalpy of reaction
(C) Gibbs energy of reaction
(D) activation energy of reaction
A first-order reaction is 25% complete in 40 minutes. Calculate the value of rate constant. In what time will the reaction be 80% complete ? [Given : $\log 2 = 0\cdot30$, $\log 3 = 0\cdot48$, $\log 4 = 0\cdot60$, $\log 5 = 0\cdot69$]
Assertion (A) : Rate constant increases with increase in temperature.
Reason (R) : Increasing the temperature of the substance increases the fraction of molecules, which collide with energies greater than activation energy.
The thermal decomposition of an acid is a first order reaction with a rate constant of $2.3 \times 10^{-3} \text{ s}^{-1}$ at a certain temperature. Calculate how long it will take for three-fourths of the initial quantity of acid to decompose.
(log 4 = 0.6021, log 2 = 0.301)
Assertion (A) : The molecularity of the reaction $\text{H}_2 + \text{Br}_2 \longrightarrow 2\text{HBr}$ appears to be 2.
Reason (R) : Two molecules of the reactants are involved in the given elementary reaction.
Assertion (A) : Order and molecularity of a reaction are always same.
Reason (R) : Complex reactions involve a sequence of elementary reactions and the slowest step is rate determining.
The rate constant for the first order decomposition of $\text{N}_2\text{O}_5$ is given by the following equation : $\log \text{k} = 23.6 - \frac{2 \times 10^4 \text{K}}{\text{T}}$. Calculate $\text{E}_a$ for this reaction. [$\text{R} = 8.314 \text{ J K}^{-1} \text{mol}^{-1}$]
The following data were obtained during the first order thermal decomposition of $\text{C}_2\text{H}_5\text{Cl}$ at a constant volume :
$\text{C}_2\text{H}_5\text{Cl (g)} \longrightarrow \text{C}_2\text{H}_4 \text{(g)} + \text{HCl (g)}$
| Experiment | Time $(\text{s}^{-1})$ | Total pressure (atm) |...
Given below is the decomposition of hydrogen peroxide in alkaline medium, which is catalysed by iodide ions :
$2\text{H}_2\text{O}_2 \xrightarrow{\text{I}^-, \text{alkaline medium}} 2\text{H}_2\text{O} + \text{O}_2$
The above reaction takes place in two steps :
Step I : $\text{H}_2\text{O}_2 + \text...
Read the following passage and answer the questions that follow :
The rate of reaction is concerned with decrease in concentration of reactants or increase in the concentration of products per unit time. It can be expressed as instantaneous rate at a particular instant of time and average rate over ...
Read the passage given below and answer the questions that follow: The rate law for a chemical reaction relates the reaction rate with the concentrations or partial pressures of the reactants. For a general reaction $\text{aA} + \text{bB} \to \text{C}$ with no intermediate steps in its reaction mech...
For the first order thermal decomposition reaction, following data was obtained :
$\text{C}_2\text{H}_5\text{Cl(g)} \longrightarrow \text{C}_2\text{H}_4\text{(g)} + \text{HCl(g)}$
| S. No. | Time(s) | Total Pressure (atm) |
| :---: | :---: | :---: |
| 1 | 0 | 0.30 |
| 2 | 30 | 0.50 |
Calculate r...
Consider the decomposition of hydrogen peroxide ($ ext{H}_2 ext{O}_2$) as per the equation given below :
$2 ext{H}_2 ext{O}_2 \xrightarrow[ ext{Alkaline medium}]{ ext{I}^-} 2 ext{H}_2 ext{O} + ext{O}_2$
The mechanism for this reaction was found to be :
Step I : $ ext{H}_2 ext{O}_2 + ext{I}^- \long...
State a condition under which a bimolecular reaction is kinetically first order reaction. Give an example. For which type of reactions, do order and molecularity have the same value ?
The following data were obtained during the first order thermal decomposition of $ ext{N}_2 ext{O}_5 ext{ (g)}$ at constant volume :
$2 ext{N}_2 ext{O}_5 ext{ (g)} \longrightarrow 2 ext{N}_2 ext{O}_4 ext{ (g)} + ext{O}_2 ext{ (g)}$
| S.No. | Time/s | Total Pressure/atm |
| :---: | :---: | :---: |
...
If the half-life period of a first order reaction is $1386\text{ s}$, then the rate constant of this reaction is :
(A) $0.5 \times 10^{-2}\text{ s}^{-1}$
(B) $0.5 \times 10^{-3}\text{ s}^{-1}$
(C) $5 \times 10^{-2}\text{ s}^{-1}$
(D) $5 \times 10^{-3}\text{ s}^{-1}$
Assertion (A) : The molecularity of the reaction $ ext{H}_2 + ext{Br}_2
ightarrow 2 ext{HBr}$ appears to be $2$.
Reason (R) : Two molecules of the reactants are involved in the given elementary reaction.
(a) In a reaction, if the concentration of reactant 'X' is tripled, the rate of reaction becomes twenty-seven times. What is the order of the reaction ?
(b) State a condition under which a bimolecular reaction is kinetically a first-order reaction. Give an example of such a reaction.
Hydrolysis of sucrose takes place by the chemical reaction :
$\text{C}_{12}\text{H}_{22}\text{O}_{11} + \text{H}_2\text{O} \text{ (excess)} \xrightarrow{\text{H}^+} \text{C}_6\text{H}_{12}\text{O}_6 + \text{C}_6\text{H}_{12}\text{O}_6$
Based on the above reaction, write :
(a) Rate law equation
(b) M...
The rate of reaction is concerned with decrease in concentration of reactants or increase in the concentration of products per unit time. It can be expressed as instantaneous rate at a particular instant of time and average rate over a large interval of time. Mathematical representation of rate of r...
(a) The conversion of molecule A to B followed second order kinetics. If concentration of A increased to three times, how will it affect the rate of formation of B ? (b) Define Pseudo first order reaction with an example.
A first order reaction is 50% complete in 30 minutes at 300 K and in 10 minutes at 320 K. Calculate activation energy ($E_a$) for the reaction. [R = 8.314 J K$^{-1}$ mol$^{-1}$] [Given : log 2 = 0.3010, log 3 = 0.4771, log 4 = 0.6021]
What happens to the rate constant k and activation energy $E_a$ as the temperature of a chemical reaction is increased ? Justify.
Unit of rate constant for the zero order reaction is :
(a) $\text{s}^{-1}$
(b) $\text{mol}^{-1}\text{ L s}^{-1}$
(c) $\text{mol}^{-2}\text{ L}^{2}\text{ s}^{-1}$
(d) $\text{mol L}^{-1}\text{ s}^{-1}$
(ii) What is the effect of temperature on rate of reaction ?
Answer the following questions (Do any two) : (a) Identify the order of reaction from the following unit for its rate constant : $\text{Lmol}^{-1}\text{s}^{-1}$ (b) The conversion of molecules A to B follow second order kinetics. If concentration of A is increased to three times, how will it affect ...
(a) The variation in the concentration (R) vs. time (t) plot is given below. Answer the following questions on the basis of the given figure : (i) Predict the order of the reaction. (ii) What is the slope of the curve ? (iii) What are the units of the rate constant k ?
Which of the following curve represents the first order reaction ?
(A) $t_{1/2}$ vs $[R]_0$ (straight line passing through origin)
(B) $t_{1/2}$ vs $[R]_0$ (horizontal line parallel to x-axis)
(C) Rate vs Concentration (horizontal line parallel to x-axis)
(D) Rate vs Concentration (exponentially dec...
Which of the following curve represents the first order reaction ?
(A) graph of $t_{1/2}$ vs $[ ext{R}]_0$ showing a linear upward trend
(B) graph of $t_{1/2}$ vs $[ ext{R}]_0$ showing a constant horizontal line
(C) graph of Rate vs Concentration showing a constant horizontal line
(D) graph of Rate ...
For a reaction : $ ext{N}_2 + 3 ext{H}_2 \longrightarrow 2 ext{NH}_3$, the rate of reaction with respect to $ ext{NH}_3$ is
(A) $+\frac{1}{3} \frac{\Delta [\text{NH}_3]}{\Delta t}$
(B) $-\frac{1}{2} \frac{\Delta [\text{NH}_3]}{\Delta t}$
(C) $+\frac{1}{4} \frac{\Delta [\text{NH}_3]}{\Delta t}$
(D) $...
For the first order thermal decomposition reaction, following data was obtained :
\(\text{C}_2\text{H}_5\text{Cl(g)} \longrightarrow \text{C}_2\text{H}_4\text{(g)} + \text{HCl(g)}\)
| S. No. | Time(s) | Total Pressure (atm) |
| :---: | :---: | :---: |
| 1 | 0 | 0.30 |
| 2 | 30 | 0.50 |
Calculate r...
Which of the following curve represents the first order reaction ?
(A) $\text{t}_{1/2}$ versus $\left[\text{R}\right]_0$
(B) $\text{t}_{1/2}$ versus $\left[\text{R}\right]_0$
(C) $\text{Rate}$ versus $\text{Concentration}$
(D) $\text{Rate}$ versus $\text{Concentration}$
The activation energy of a reaction can be determined from the slope of which of the following curves ?
(A) $\ln k$ vs. $ ext{T}$
(B) $\ln k$ vs. $\frac{1}{ ext{T}}$
(C) $\ln \frac{k}{ ext{T}}$ vs. $ ext{T}$
(D) $\frac{ ext{T}}{\ln k}$ vs. $\frac{1}{ ext{T}}$
(a) Define activation energy.
(b) Write the unit of rate constant for
(i) zero order reaction, (ii) second order reaction.
(a) Define Collision frequency.
(b) Write the units of
(i) first order reaction and (ii) zero order reaction
(a) Define Effective collision.
(b) Write the unit of
(i) second order reaction and (ii) zero order reaction
For a first order reaction, show that the time required for $99%$ completion is twice the time required for the completion of $90%$ of the reaction. $[\log 10 = 1]$
Answer the following :\n(a) Find the half-life of a first order reaction with a rate constant given as $2\cdot31 \times 10^{-6}\text{ s}^{-1}$.\n(b) What is the effect of adding a catalyst on the activation energy $(E_a)$ ?\n(c) Why does the rate of a reaction increase with the rise in temperature ?
Assertion (A) : Rate of reaction increases with an increase in temperature.
Reason (R) : Number of effective collisions decreases with an increase in temperature.
Write any two differences between the order of a reaction and molecularity of a reaction.
A first order reaction is $50%$ complete in $20$ minutes. Calculate the time for $75%$ completion of the reaction. $[\log 4 = 0\cdot6]$
For a reaction $3\text{A} \rightarrow 2\text{B}$, the rate of reaction $\frac{+\text{d}[\text{B}]}{\text{dt}}$ is equal to :
(A) $-\frac{3}{2} \frac{\text{d}[\text{A}]}{\text{dt}}$
(B) $-\frac{2}{3} \frac{\text{d}[\text{A}]}{\text{dt}}$
(C) $-\frac{1}{3} \frac{\text{d}[\text{A}]}{\text{dt}}$
(D) $+2...
Assertion (A) : Order of reaction is applicable to elementary as well as complex reactions.
Reason (R) : Order of a reaction is an experimental quantity.
For a reaction $\text{A} + \text{B} \rightarrow \text{Products}$, the rate law is :
$\text{Rate} = \text{k}[\text{A}][\text{B}]^{\frac{3}{2}}$
Write the overall order of the reaction. Can this reaction be an elementary reaction ? Give reason in support of your answer.
The half-life period of a radioactive element is $1.5 imes 10^{10}$ years. Calculate the time in which the activity of the element is reduced to $75%$ of its original value.
[Given : $\log 2 = 0 \cdot 30$, $\log 3 = 0 \cdot 48$, $\log 4 = 0 \cdot 60$]
For the reaction $2 ext{A}
ightarrow 3 ext{B}$, the rate of reaction $+\frac{ ext{d}[ ext{B}]}{ ext{dt}}$ is equal to :
(A) $-\frac{3}{2} \frac{ ext{d}[ ext{A}]}{ ext{dt}}$
(B) $-\frac{2}{3} \frac{ ext{d}[ ext{A}]}{ ext{dt}}$
(C) $-\frac{1}{2} \frac{ ext{d}[ ext{A}]}{ ext{dt}}$
(D) $+3 \frac{ ext{d...
For a reaction $ ext{A} + ext{B}
ightarrow ext{Products}$, the rate law is :
$\text{Rate} = ext{k}[ ext{A}][ ext{B}]^{\frac{3}{2}}$
Write the overall order of the reaction. Can this reaction be an elementary reaction ? Give reason in support of your answer.
The half-life period of a radioactive element is $1\cdot5 \times 10^{10}\text{ years}$. Calculate the time in which the activity of the element is reduced to $75%$ of its original value.
[Given : $\log 2 = 0\cdot30$, $\log 3 = 0\cdot48$, $\log 4 = 0\cdot60$]
The half-life periods of decomposition of $\text{NH}_3$ for different initial pressures are given below :
| $\text{p (torr)}$ | $704$ | $75$ | $34 \cdot 5$ |
| :--- | :---: | :---: | :---: |
| $\text{t}_{1/2} \text{ (min)}$ | $80$ | $80$ | $80$ |
The order of the reaction is :
(A) zero order
(B) f...
For a reaction $\text{A} + \text{B} \rightarrow \text{Products}$, the rate law is :\n$\text{Rate} = \text{k}[\text{A}][\text{B}]^{\frac{3}{2}}$\nWrite the overall order of the reaction. Can this reaction be an elementary reaction ? Give reason in support of your answer.
The half-life period of a radioactive element is $1\cdot5 \times 10^{10}$ years. Calculate the time in which the activity of the element is reduced to $75% ext{}$ of its original value.
[Given : $\log 2 = 0\cdot30$, $\log 3 = 0\cdot48$, $\log 4 = 0\cdot60$]
The rate of a first order reaction is $5\cdot 6 \times 10^{-4}\text{ mol L}^{-1}\text{ s}^{-1}$, when the concentration of reactant is $0\cdot 2\text{ mol L}^{-1}$. The rate constant 'k' is :
(A) $5\cdot 6 \times 10^{-3}\text{ s}^{-1}$
(B) $2\cdot 8 \times 10^{-4}\text{ s}^{-1}$
(C) $2\cdot 8 \times...
Assertion ($A$) : For complex reaction, order of reaction is given by the slowest step.
Reason ($R$) : Order of a reaction is an experimental quantity.
Consider the decomposition of hydrogen peroxide ($ ext{H}_2 ext{O}_2$) as per the equation given below :
$2 ext{H}_2 ext{O}_2 \xrightarrow[\text{Alkaline medium}]{\text{I}^-} 2 ext{H}_2 ext{O} + ext{O}_2$
The mechanism for this reaction was found to be :
Step I : $ ext{H}_2 ext{O}_2 + ext{I}^- \lo...
The rate of a first order reaction is $5.6 imes 10^{-4} ext{ mol L}^{-1} ext{ s}^{-1}$, when the concentration of reactant is $0.2 ext{ mol L}^{-1}$. The rate constant ' $k$ ' is :
(A) $5.6 imes 10^{-3} ext{ s}^{-1}$
(B) $2.8 imes 10^{-4} ext{ s}^{-1}$
(C) $2.8 imes 10^{-5} ext{ s}^{-1}$
(D) $2....
The rate of a first order reaction is $5.6 \times 10^{-4}\text{ mol L}^{-1}\text{ s}^{-1}$, when the concentration of reactant is $0.2\text{ mol L}^{-1}$. The rate constant '$k$' is :
(A) $5.6 \times 10^{-3}\text{ s}^{-1}$
(B) $2.8 \times 10^{-4}\text{ s}^{-1}$
(C) $2.8 \times 10^{-5}\text{ s}^{-1}$...
(a) Define order of a reaction.
(b) The rate for the following reaction is given by : $\text{A} + \text{B} \to \text{C}$
$$\text{Rate} = \text{k}[\text{A}][\text{B}]^2$$
(i) How is the rate of reaction affected if we double the concentration of $\text{B}$ ?
(ii) Write the overall order of a reaction...
The rate of the chemical reaction doubles when the temperature is raised from $298\text{ K}$ to $308\text{ K}$. Calculate activation energy ($E_\text{a}$) for this reaction assuming that it does not change with temperature.
(Given : $R = 8.314\text{ J mol}^{-1}\text{ K}^{-1}$, $\log 2 = 0.30$)
Define order of a reaction.
The rate for the following reaction is given by : $\text{A} + \text{B} \rightarrow \text{C}$
$\text{Rate} = \text{k}[\text{A}][\text{B}]^2$
(i) How is the rate of reaction affected if we double the concentration of $\text{B}$ ?
(ii) Write the overall order of a reaction if '$\text{A}$' is present in...
(a) Define order of a reaction.
(b) The rate for the following reaction is given by : $\text{A} + \text{B} \rightarrow \text{C}$
$$\text{Rate} = \text{k}[\text{A}][\text{B}]^2$$
(i) How is the rate of reaction affected if we double the concentration of $\text{B}$ ?
(ii) Write the overall order of a ...
A reaction is of first order with respect to $ ext{A}$ and of second order with respect to $ ext{B}$. What will happen to the rate of reaction if (i) only the concentration of $ ext{B}$ is increased to three times, and (ii) $ ext{A}$ is taken in excess ?
A reaction is of first order with respect to $\text{A}$ and of second order with respect to $\text{B}$. How is the rate of reaction affected, when the concentration of (i) both $\text{A}$ and $\text{B}$ are doubled, and (ii) $\text{A}$ is doubled and $\text{B}$ is reduced to half ?
A reaction $\text{A} \rightarrow \text{B}$ follows second order kinetics. How will the rate of reaction be affected if the concentration of (i) $\text{A}$ is increased by three times, and (ii) $\text{A}$ is reduced to half ?
Consider the graph for the reaction $\text{H}_2 + \text{I}_2 \rightleftharpoons 2\text{HI}$
I. Calculate enthalpy of reaction and activation energy for the backward reaction.
II. How will the catalyst affect the rate of this reaction? Explain.
(for visually challenged learners)
I. Define activation ...
B.
I. Consider the following first order thermal decomposition of $\text{SO}_2\text{Cl}_2$ at a constant volume
$\text{SO}_2\text{Cl}_2\text{ (g)} \rightarrow \text{SO}_2\text{ (g)} + \text{Cl}_2\text{ (g)}$
If the total pressure of the gases is found to be $200\text{ torr}$ after $10\text{ seconds}...
(a) The rate law for the reaction :
$ ext{CH}_3 ext{COOCH}_3 + ext{H}_2 ext{O} \xrightarrow{ ext{H}^+} ext{CH}_3 ext{COOH} + ext{CH}_3 ext{OH}$ is
Rate = $ ext{k } [ ext{CH}_3 ext{COOCH}_3] [ ext{H}_2 ext{O}]^0$
What would be the effect on the rate if
(i) concentration of $ ext{CH}_3 ext{COOCH}_3...
Temperature dependence of rate constants is described by Arrhenius equation :
$k = A \ e^{- ext{Ea/RT}}$
$ ext{E}_ ext{a}$ corresponds to the activation energy and A corresponds to the collision frequency. The equation clearly shows that increase of temperature or lowering of $ ext{E}_ ext{a}$ will ...
The rate of reaction X + Y $\rightarrow$ products, is given by the equation
$$\text{Rate} = \text{k}[X]\ [Y].$$
If Y is taken in large excess, the order of the reaction would be
(A) 0
(B) 1
(C) 2
(D) $\frac{1}{2}$
Assertion (A) : In a first order reaction, if the concentration of the reactant is doubled, its half-life is also doubled.
Reason (R) : The half-life of a reaction does not depend upon the initial concentration of the reactant in a first order reaction.
(a) A reaction is second order in ‘A’ and first order in ‘B’. How is the rate affected when the concentrations of both ‘A’ and ‘B’ are doubled ?
(b) Write the unit of ‘$k$’ for zero order reaction.
The rate constant of a first order reaction increases from $0.04\text{ s}^{-1}$ to $0.08\text{ s}^{-1}$ when the temperature increases from $27^\circ\text{C}$ to $37^\circ\text{C}$. Calculate the energy of activation ($E_a$).
[Given : $2.303\text{R} = 19.15\text{ JK}^{-1}\text{mol}^{-1}$]
[$\log 2 =...
(a) Reactant 'A' underwent a decomposition reaction. The concentration of 'A' was measured periodically and recorded in the table given below :
| $\text{Time} / \text{Hours}$ | $[\text{A}] / \text{M}$ |
| :---: | :---: |
| $0$ | $0\cdot40$ |
| $1$ | $0\cdot20$ |
| $2$ | $0\cdot10$ |
| $3$ | $0\cdot...
(ii) Account for the following :
(I) We cannot determine the order of a reaction by taking into consideration the balanced chemical equation.
(ii) For a reaction :
$2\text{H}_2\text{O}_2 \xrightarrow{\text{I}^-} 2\text{H}_2\text{O} + \text{O}_2$
the proposed mechanism is as given below :
(I) $\text{H}_2\text{O}_2 + \text{I}^- \longrightarrow \text{H}_2\text{O} + \text{IO}^-$ (slow)
(II) $\text{H}_2\text{O}_2 + \text{IO}^- \longrightarrow ...
(a) Reactant 'A' underwent a decomposition reaction. The concentration of 'A' was measured periodically and recorded in the table given below :
| Time / Hours | [A] / M |
|---|---|
| 0 | 0.40 |
| 1 | 0.20 |
| 2 | 0.10 |
| 3 | 0.05 |
Based on the above data, predict the order of the reaction and wr...
(a) The reaction between $\text{A}_2(\text{g})$ and $\text{B}_2(\text{g})$ was carried out in a sealed isothermal container. The rate law for the reaction was found to be :
$$\text{Rate} = \text{k}[\text{A}_2] [\text{B}_2]$$
If $1$ mole of $\text{A}_2(\text{g})$ was added to the reaction chamber and...
(a) (ii) (I) Account for the following :
We cannot determine the order of a reaction by taking into consideration the balanced chemical equation.
(b) (ii) For a reaction :
$$2\text{H}_2\text{O}_2 \xrightarrow{\text{I}^-} 2\text{H}_2\text{O} + \text{O}_2$$
the proposed mechanism is as given below :
(I) $\text{H}_2\text{O}_2 + \text{I}^- \longrightarrow \text{H}_2\text{O} + \text{IO}^-$ (slow)
(II) $\text{H}_2\text{O}_2 + \text{IO}^- \longright...
(a) Write the rate law expression for the reaction $2\text{HI} \rightarrow \text{H}_2 + \text{I}_2$, if the order of the reaction is zero.
(b) What is the effect of temperature on the rate of reaction ? Write a mathematical expression for the same.
(a) Define rate constant.
(b) Identify the reaction order which has a rate constant of $4\cdot5 \times 10^{-5}\text{ L mol}^{-1}\text{ s}^{-1}$.
(a) Give any two differences between order and molecularity of a reaction.
(b) For a reaction $\text{X} + \text{Y} \rightarrow \text{Z}$, in which both $\text{X}$ and $\text{Y}$ follow first order kinetics; if the concentration of $\text{X}$ is increased $2$ times and concentration of $\text{Y}$ is ...
The unit of rate and rate constant are same for a :
(A) First order reaction
(B) Second order reaction
(C) Zero order reaction
(D) Third order reaction
The rate of a reaction : $\text{A} + \text{B} \longrightarrow \text{product}$ is given below as a function of different initial concentrations of A and B.
\begin{tabular}{|c|c|c|c|}
\hline
Experiment & $[\text{A}] / \text{mol L}^{-1}$ & $[\text{B}] / \text{mol L}^{-1}$ & $\text{Initial Rate} / \text...
The value of rate constant for a pseudo first order reaction :
(A) depends only on temperature.
(B) depends on the concentration of reactants present in small amount.
(C) depends on the concentration of reactants present in large excess.
(D) is not dependent on the concentration of reactants.
The rate of a reaction :\n$\text{A} + \text{B} \longrightarrow \text{product}$\nis given below as a function of different initial concentrations of A and B.\n\n| Experiment | $\text{[A] / mol L}^{-1}$ | $\text{[B] / mol L}^{-1}$ | Initial $\text{Rate/mol L}^{-1}\text{ min}^{-1}$ |\n| :---: | :---: |...
In the Arrhenius equation $\text{k} = \text{Ae}^{-\text{E}_\text{a}/\text{RT}}$, 'A' represents :
(A) effective collisions
(B) frequency factor
(C) fraction of collisions
(D) threshold energy
Assertion ($A$) : Molecularity of reaction is determined experimentally.
Reason ($R$) : Molecularity is applicable only for an elementary reaction and not for a complex reaction.
The rate of a reaction :
$ ext{A} + ext{B} \longrightarrow ext{product}$
is given below as a function of different initial concentrations of $ ext{A}$ and $ ext{B}$.
Experiment | $[ ext{A}] / ext{mol L}^{-1}$ | $[ ext{B}] / ext{mol L}^{-1}$ | Initial Rate$/ ext{mol L}^{-1} ext{ min}^{-1}$
1 | $0...
The activation energy ($E_a$) of a reaction can be determined from the slope of which of the following plots ?
(A) $\ln k$ vs. T
(B) $\frac{\ln k}{\text{T}}$ vs. T
(C) $\ln k$ vs. $\frac{1}{\text{T}}$
(D) $\frac{\text{T}}{\ln k}$ vs. $\frac{1}{\text{T}}$
The following data were obtained during the first order thermal decomposition of $\text{N}_2\text{O}_5 \text{ (g)}$ at constant volume :
$2\text{N}_2\text{O}_5 \text{ (g)} \longrightarrow 2\text{N}_2\text{O}_4 \text{ (g)} + \text{O}_2 \text{ (g)}$
| S.No. | Time/s | Total Pressure/atm |
| :---: | ...
Unit of rate constant 'k' for a second order reaction is :
(A) $\text{s}^{-1}$
(B) $\text{mol L}^{-1} \text{s}^{-1}$
(C) $\text{mol}^{-1} \text{L s}^{-1}$
(D) $\text{mol}^{-2} \text{L s}^{-1}$
Which of the following is the slope of the first order reaction in the plot of $\ln[\text{R}]$ vs. time ?
(A) $+ k$
(B) $\frac{+ k}{2 \cdot 303}$
(C) $- k$
(D) $\frac{- k}{2 \cdot 303}$
Why is molecularity applicable only for elementary reactions and order is applicable for elementary as well as complex reactions ?
Assertion (A) : The molecularity of the reaction $\text{H}_2 + \text{Br}_2 \rightarrow 2\text{HBr}$ appears to be 2.
Reason (R) : Two molecules of the reactants are involved in the given elementary reaction.
The following data were obtained during the kinetic studies of the reaction :
$$\text{A} + 2\text{B} \rightarrow \text{C} + 2\text{D}$$
Determine the order of reaction with respect to each reactant and the overall order of the reaction. Write the rate law expression for the reaction.
By giving reasons, explain that how the rate of reaction for a given reaction will be affected when :
(a) the temperature is increased.
(b) catalyst is added.
The following data were obtained during the kinetic studies of the reaction :
$\text{A} + 2\text{B} \rightarrow \text{C} + 2\text{D}$
[Table data included]
Determine the order of reaction with respect to each reactant and the overall order of the reaction. Write the rate law expression for the re...
If the half-life period of a first order reaction is $2772\text{ s}$, then the rate constant of this reaction is :
(A) $2.5 \times 10^{-4}\text{ s}^{-1}$
(B) $2.5 \times 10^{-3}\text{ s}^{-1}$
(C) $25 \times 10^{-4}\text{ s}^{-1}$
(D) $25 \times 10^{-3}\text{ s}^{-1}$
The following results have been obtained during the kinetic studies of the reaction :
$$2\text{A} + \text{B} \rightarrow \text{C} + \text{D}$$
| Experiment | $[\text{A}] / \text{mol L}^{-1}$ | $[\text{B}] / \text{mol L}^{-1}$ | Initial rate of formation of $\text{D} \; (\text{mol L}^{-1} \text{min...
A first-order reaction is found to have a rate constant, $k = 5.5 \times 10^{-14} \text{ s}^{-1}$. The time taken for completion of the reaction is:
a. $1.26 \times 10^{13} \text{ s}$
b. $2.52 \times 10^{13} \text{ s}$
c. $0.63 \times 10^{13} \text{ s}$
d. It never goes to completion
Assertion (A): The half- life for a zero order reaction is independent of the initial concentration of the reactant.
Reason (R): For a zero order reaction, $\text{Rate} = k$
Select the most appropriate answer from the options given below:
a. Both A and R are true and R is the correct explanation of...
Dependence of the rate of reaction on the concentration of reactants, temperature, and other factors is the most general method for weeding out unsuitable reaction mechanisms. The term mechanism means all the individual collisional or elementary processes involving molecules (atoms, radicals, and io...
(a) (i) What is rate of reaction ? Write two factors that affect the rate of reaction.
(a) (ii) For a reaction,
$2\text{H}_2\text{O}_2 \xrightarrow{\text{I}^-, \text{OH}^-} 2\text{H}_2\text{O} + \text{O}_2$
the proposed mechanism is as given below :
(1) $\text{H}_2\text{O}_2 + \text{I}^- \rightarrow \text{H}_2\text{O} + \text{IO}^-$ (slow step)
(2) $\text{H}_2\text{O}_2 + \text{IO}^- ...
(b) (i) Define pseudo first order reaction with one example. (ii) The rate constant of a first order reaction increases from $4 \times 10^{-2}$ to $8 \times 10^{-2}$ when the temperature changes from $27^{\circ}\text{C}$ to $37^{\circ}\text{C}$. Calculate its energy of activation ($E_a$). (Given : $...
When a catalyst increases the rate of a chemical reaction, then the rate constant (k) :
(A) remains constant
(B) decreases
(C) increases
(D) may increase or decrease depending on the order of the reaction
Assertion (A) : Order of reaction and molecularity are always same for complex reactions.
Reason (R) : Order is determined experimentally and molecularity is applicable only for elementary reactions.
Assertion (A) : Rate of reaction increases with increase in temperature.
Reason (R) : Number of effective collisions increase with increase in temperature.
The half life of a first order reaction with rate constant (k) of $3 \text{ min}^{-1}$ is :
(A) $0\cdot693 \text{ min}$
(B) $2\cdot31 \text{ min}$
(C) $6\cdot93 \text{ min}$
(D) $0\cdot231 \text{ min}$
Assertion (A) : Rate of reaction decreases with increase in temperature. Reason (R) : Number of effective collisions increases with increase in temperature.
(a) In a reaction, if the concentration of reactant 'X' is tripled, the rate of reaction becomes twenty-seven times. What is the order of the reaction?
For a chemical reaction, $\text{A} \to \text{B}$, it was observed that the rate of reaction doubles when the concentration of A is increased four times. The order of the reaction is :
(A) 2
(B) 1
(C) 1/2
(D) Zero
For a chemical reaction, $A \rightarrow B$, it was observed that the rate of reaction doubles when the concentration of A is increased four times. The order of the reaction is : (A) 2 (B) 1 (C) $1/2$ (D) Zero
For a chemical reaction, $A \to B$, it was observed that the rate of reaction doubles when the concentration of A is increased four times. The order of the reaction is : (A) 2 (B) 1 (C) 1/2 (D) Zero
Hydrolysis of ethyl ethanoate takes place by the chemical reaction : $\text{CH}_3\text{COOC}_2\text{H}_5 + \text{H}_2\text{O (excess)} \xrightarrow{\text{H}^+} \text{CH}_3\text{COOH} + \text{C}_2\text{H}_5\text{OH}$. Based on the above reaction, write : (a) What do you call such reactions ? (b) Rate...
Rate of reaction depends upon the experimental conditions such as concentration of reactants, temperature and catalyst. Mathematical representation of rate of a reaction is given by rate law : Rate = k [A]^p [B]^q. A balanced chemical equation never gives us a true picture of how a reaction takes pl...
For the reaction $3\text{A} \rightarrow 2\text{B}$, rate of reaction $+\frac{\text{d[B]}}{\text{dt}}$ is equal to
(a) $\frac{-3}{2} \frac{\text{d[A]}}{\text{dt}}$
(b) $\frac{-2}{3} \frac{\text{d[A]}}{\text{dt}}$
(c) $\frac{-1}{3} \frac{\text{d[A]}}{\text{dt}}$
(d) $+\frac{2\text{d[A]}}{\text{dt}}$
The slope in the plot of $\ln[\text{R}]$ vs. time for a first order reaction is
(a) $\frac{+\text{k}}{2.303}$
(b) $-\text{k}$
(c) $\frac{-\text{k}}{2.303}$
(d) $+\text{k}$
(i) What is average rate of reaction ?
(ii) Write two factors that affect the rate of reaction.
(iii) (1) What happens to rate of reaction for zero order reaction ? (2) What is the unit of k for zero order reaction ?
(iii) (1) For a reaction P + 2Q $\longrightarrow$ Products Rate = k[P]$^{1/2}$ [Q]$^1$. What is the order of the reaction ? (2) Define pseudo first order reaction with an example.
A first order reaction takes 30 minutes for 50% completion. The value of rate constant k would be :
(a) $2.5 \times 10^{-3} \text{ min}^{-1}$
(b) $2.75 \times 10^{-4} \text{ min}^{-1}$
(c) $1.25 \times 10^{-3} \text{ min}^{-1}$
(d) $2.31 \times 10^{-3} \text{ min}^{-1}$
(i) What is average rate of reaction?
(ii) Write two factors that affect the rate of reaction.
(iii) (1) What happens to rate of reaction for zero order reaction?
(2) What is the unit of k for zero order reaction?
OR
(iii) (1) For a reaction P + 2Q $\longrightarrow$ Products
Rate = k[P]$^{1/2}$ [Q]$...
Which of the following statement is true?
(a) molecularity of reaction can be zero or a fraction.
(b) molecularity has no meaning for complex reactions.
(c) molecularity of a reaction is an experimental quantity
(d) reactions with the molecularity three are very rare but are fast.
If the initial concentration of substance A is 1.5 M and after 120 seconds the concentration of substance A is 0.75 M, the rate constant for the reaction if it follows zero-order kinetics is:
(a) $0.00625 \text{ mol L}^{-1} \text{s}^{-1}$ (b) $0.00625 \text{ s}^{-1}$ (c) $0.00578 \text{ mol L}^{-1} ...
a. Radioactive decay follows first-order kinetics. The initial amount of two radioactive elements X and Y is 1 gm each. What will be the ratio of X and Y after two days if their half-lives are 12 hours and 16 hours respectively?
b. The hypothetical reaction P + Q $\rightarrow$ R is half order w.r.t ...
The rate constants of a reaction at 200K and 500K are $0.02\text{s}^{-1}$ and $0.20\text{s}^{-1}$ respectively. Calculate the value of $\text{Ea}$ (Given $2.303\text{R} = 19.15\text{ JK}^{-1}\text{mol}^{-1}$)
The slope in the plot of [R] vs. time for a zero order reaction is
(a) $\frac{+ k}{2.303}$
(b) $- k$
(c) $\frac{- k}{2.303}$
(d) $+ k$
For a reaction $2\text{A} \rightarrow 3\text{B}$, rate of reaction $-\frac{\text{d[A]}}{\text{dt}}$ is equal to
(a) $\frac{+3}{2} \frac{\text{d[B]}}{\text{dt}}$
(b) $\frac{+2}{3} \frac{\text{d[B]}}{\text{dt}}$
(c) $\frac{+1}{3} \frac{\text{d[B]}}{\text{dt}}$
(d) $+ \frac{2\text{d[B]}}{\text{dt}}$
The slope in the plot of $\log \frac{[\text{R}]_0}{[\text{R}]}$ vs. time for a first order reaction is
(a) $\frac{+ k}{2.303}$
(b) $+ k$
(c) $\frac{- k}{2.303}$
(d) $- k$
For the reaction $3\text{A} \rightarrow 2\text{B}$, rate of reaction $-\frac{d[\text{A}]}{dt}$ is equal to (a) $\frac{+3}{2} \frac{d[\text{B}]}{dt}$ (b) $\frac{+2}{3} \frac{d[\text{B}]}{dt}$ (c) $\frac{+1}{3} \frac{d[\text{B}]}{dt}$ (d) $\frac{+1}{2} \frac{d[\text{B}]}{dt}$
The unit of rate constant and rate of reaction are identical for a:
(a) zero order reaction
(b) first order reaction
(c) second order reaction
(d) third order reaction
The rate constant of a reaction is $2 \times 10^{-2} \text{ s}^{-1}$ at 300 K and $8 \times 10^{-2} \text{ s}^{-1}$ at 340 K. Calculate the energy of activation of the reaction.
[R = 8.314 $\text{JK}^{-1} \text{ mol}^{-1}$], [log 2 = 0.3010, log 4 = 0.6021]
The unit of the rate of reaction is the same as that of the rate constant for a :
(a) first order reaction
(b) second order reaction
(c) zero order reaction
(d) it cannot be same
The rate of reaction $\text{A} + \text{B} \longrightarrow \text{Products}$, is given by the equation $r = k[\text{A}][\text{B}]$. If $\text{B}$ is taken in large excess, the order of reaction would be :
(a) 2
(b) 0
(c) 1
(d) Cannot be predicted
The half-life of a first order reaction is 60 minutes. How long will it take to consume 90% of the reactant?
[Given : $\log 2 = 0.3010$, $\log 3 = 0.4771$, $\log 10 = 1$]
The half-life for a zero order reaction equals : (a) $\frac{2k}{R}$ (b) $\frac{1}{2} \frac{k}{R^2}$ (c) $\frac{R^2}{2k}$ (d) $\frac{R}{2k}$ where R is the initial concentration.
For the reaction A + 2B $\longrightarrow$ C + D, the rate law is given by r = k[A] [B]$^{2}$, the concentration of A is kept constant while that of B is doubled. The rate of the reaction will : (a) double (b) become half (c) not change (d) quadruple
If the initial concentration is reduced to $\frac{1}{4}$ th in a zero order reaction, then the time taken for half the reaction to complete : (a) remains the same (b) reduces to one-fourth (c) increases four times (d) doubles
For a zero order reaction of the type $A \rightarrow \text{products}$, the rate equation may be expressed as :
(a) $k = \frac{[A]_0 - [A]}{t}$
(b) $k = \frac{[A] - [A]_0}{t}$
(c) $k = \frac{[A]_0 - [A]}{2t}$
(d) $k = \frac{[A]_0 - [A]}{2} \cdot t$
(a) For the reaction $2\text{N}_2\text{O}_{5(g)} \rightarrow 4\text{NO}_{2(g)} + \text{O}_{2(g)}$ at $318\text{ K}$ calculate the rate of reaction if rate of disappearance of $\text{N}_2\text{O}_{5(g)}$ is $1.4 \times 10^{-3}\text{ m s}^{-1}$. (b) For a first order reaction derive the relationship $...
What happens to the rate constant k and activation energy $\text{E}_a$ as the temperature of a chemical reaction is increased ? Justify.
(a) For the reaction $2\text{N}_2\text{O}_{5(\text{g})} \rightarrow 4\text{NO}_{2(\text{g})} + \text{O}_{2(\text{g})}$ at $318 \text{ K}$ calculate the rate of reaction if rate of disappearance of $\text{N}_2\text{O}_{5(\text{g})}$ is $1.4 \times 10^{-3} \text{ m s}^{-1}$. (b) For a first order reac...
(a) For the reaction $2\text{N}_2\text{O}_{5(g)} \to 4\text{NO}_{2(g)} + \text{O}_{2(g)}$ at $318 \text{ K}$ calculate the rate of reaction if rate of disappearance of $\text{N}_2\text{O}_{5(g)}$ is $1.4 \times 10^{-3} \text{ m s}^{-1}$. (b) For a first order reaction derive the relationship $t_{99%...
A reaction follows second order kinetics. How is the rate of reaction affected if the concentration of the reactant is reduced to half ? Choose the correct value from the following :
(a) four times
(b) eight times
(c) $\frac{1}{4}$ of the original value
(d) three times
(a) Write the mathematical relation between rate constant and half-life period of a zero order reaction.
(b) Define Pseudo first order reaction with an example.
The rate law for a particular reaction is given as $\text{rate} = k[A][B]^2$.
How is the rate of reaction affected if we double the concentration of B ?
Choose the correct option :
(a) two times
(b) four times
(c) three times
(d) becomes half $\left(\frac{1}{2}\right)$
Unit of rate constant for the zero order reaction is :
(a) $ ext{s}^{-1}$ (b) $ ext{mol}^{-1} ext{L s}^{-1}$
(c) $ ext{mol}^{-2} ext{L}^2 ext{s}^{-1}$ (d) $ ext{mol L}^{-1} ext{s}^{-1}$
(a) Write the mathematical relation between rate constant and half-life of a first order reaction.
(b) What is collision frequency?
(a) Write the Arrhenius equation.
(b) Define half-life of a reaction.
The unit of zero order reaction is :
(a) $\text{s}^{-1}$
(b) $\text{L}^2 \text{ mol}^{-1} \text{ s}^{-1}$
(c) $\text{mol L}^{-1} \text{ s}^{-1}$
(d) $\text{L s}^{-1}$
A reaction is second order with respect to a reactant. How is the rate of reaction affected if the concentration of the reactant is :
(i) doubled ?
(ii) reduced to half ?
The rate constant of a first order reaction increases from $2 \times 10^{-2} \text{ s}^{-1}$ to $4 \times 10^{-2} \text{ s}^{-1}$ when the temperature changes from $300 \text{ K}$ to $310 \text{ K}$. Calculate the energy of activation ($E_a$). [$\log 2 = 0.3010, \log 3 = 0.4771, \log 4 = 0.6021$] [$...
Define rate of reaction. Write two factors that affect the rate of reaction.
A first order reaction is 50% complete in 40 minutes. Calculate the time required for the completion of 90% of reaction. [Given : $\log 2 = 0.3010, \log 10 = 1$]
(a) A reaction is second order in X and first order in Y. How is the rate affected when the concentrations of both X and Y are doubled?
(b) Write the units of 'k' for
(i) zero order reaction
(ii) first order reaction
A first order reaction is 50% complete in 40 minutes. Calculate the time required for the completion of 90% of reaction. [Given : log 2 = 0.3010, log 10 = 1]
A first order reaction is $50%$ complete in $40$ minutes. Calculate the time required for the completion of $90%$ of reaction.
[Given : $\log 2 = 0.3010, \log 10 = 1$]
In the given reaction
$\text{N}_2\text{ (g)} + 3\text{H}_2\text{ (g)} \longrightarrow 2\text{NH}_3\text{ (g)}$
the rate of formation of $\text{NH}_3$ is $3.6 \times 10^{-4}\text{ mol L}^{-1}\text{ s}^{-1}$.
Calculate the
(i) rate of reaction, and
(ii) rate of disappearance of $\text{H}_2\text{ (g)}$...
Which radioactive isotope would have the longer half- life $^{15}\text{O}$ or $^{19}\text{O}$? (Given rate constants for $^{15}\text{O}$ and $^{19}\text{O}$ are $5.63 \times 10^{-3} \text{ s}^{-1}$ and $k = 2.38 \times 10^{-2} \text{s}^{-1}$ respectively.)
a. $^{15}\text{O}$
b. $^{19}\text{O}$
c. Bo...
For the reaction, $\text{A} + 2\text{B} \rightarrow \text{AB}_2$, the order w.r.t. reactant A is 2 and w.r.t. reactant B. What will be change in rate of reaction if the concentration of A is doubled and B is halved?
a. increases four times
b. decreases four times
c. increases two times
d. no change
Arrhenius equation can be represented graphically as follows:
The (i) intercept and (ii) slope of the graph are:
a. (i) ln A (ii) Ea/R
b. (i) A (ii) Ea
c. (i)ln A (ii) -Ea/R
d. (i) A (ii) -Ea
*FOR VISUALLY CHALLENGED LEARNERS
The unit of rate constant for the reaction 2A + 2B $\rightarrow$ A$_2$B$_2$ which has rate = k [A]$^2$[B] is:
a. mol L$^{-1}$s$^{-1}$
b. s$^{-1}$
c. mol L$^{-1}$
d. mol$^{-2}$ L$^2$ s$^{-1}$
Explain how and why will the rate of reaction for a given reaction be affected when a. a catalyst is added b. the temperature at which the reaction was taking place is decreased
(a) What is the effect of temperature on the rate constant of a reaction ?
(b) For a reaction $A + B \rightarrow \text{Product}$, the rate law is given by, $\text{Rate} = k[A]^2 [B]^{1/2}$. What is the order of the reaction ?
(c) How order and molecularity are different for complex reactions ?
(d) A...
(a) What is the effect of temperature on the rate constant of a reaction? (b) For a reaction A + B $\rightarrow$ Product, the rate law is given by, Rate = k[A]$^2$ [B]$^{1/2}$. What is the order of the reaction? (c) How order and molecularity are different for complex reactions? (d) A first order re...
(i) Calculate the overall order of a reaction which has the following rate expression :
Rate = $\text{k[A]}^{1/2} \text{[B]}^{3/2}$
(iv) (a) A first order reaction takes $77.78$ minutes for $50%$ completion. Calculate the time required for $30%$ completion of this reaction. $(\log 10 = 1, \log 7 = 0.8450)$
(b) A first order reaction has a rate constant $1 \times 10^{-3}$ per sec. How long will $5 \text{ g}$ of this reactant take to reduce to $3 \text{ g}$ ? $(\log 3 = 0.4771; \log 5 = 0.6990)$
Calculate the overall order of a reaction which has the following rate expression : $\text{Rate} = \text{k[A]}^{1/2} \text{[B]}^{3/2}$
A first order reaction takes $77.78$ minutes for $50%$ completion. Calculate the time required for $30%$ completion of this reaction. $(\log 10 = 1, \log 7 = 0.8450)$
A first order reaction has a rate constant $1 \times 10^{-3}$ per sec. How long will $5$ g of this reactant take to reduce to $3$ g ? $(\log 3 = 0.4771; \log 5 = 0.6990)$
Answer the following questions (Do any two) :
(a) Identify the order of reaction from the following unit for its rate constant :
$\text{L} \text{mol}^{-1} \text{s}^{-1}$
(b) The conversion of molecules A to B follow second order kinetics. If concentration of A is increased to three times, how will i...
(a) For a reaction $\text{R} \rightarrow \text{P}$, half life ($t_{1/2}$) is independent of the initial concentration of reactants. What is the order of the reaction ? (b) Write one difference between order and molecularity of a reaction.
(b) A first order reaction takes 24 minutes for 50% decomposition. Calculate the time required for 25% decomposition. (Given : log 4 = 0.6021, log 3 = 0.4771)
(a) For a reaction $R \rightarrow P$, half life $(t_{1/2})$ is independent of the initial concentration of reactants. What is the order of the reaction ?
(b) Write one difference between order and molecularity of a reaction.
OR (b) A first order reaction takes 24 minutes for 50% decomposition. Calculate the time required for 25% decomposition. (Given : $\log 4 = 0\cdot6021$, $\log 3 = 0\cdot4771$)
(a) For a reaction $R \to P$, half life $(t_{1/2})$ is independent of the initial concentration of reactants. What is the order of the reaction ?
(b) Write one difference between order and molecularity of a reaction.
(a) The variation in the concentration ($\text{R}$) vs. time ($\text{t}$) plot is given below. Answer the following questions on the basis of the given figure :
(i) Predict the order of the reaction.
(ii) What is the slope of the curve ?
(iii) What are the units of the rate constant $\text{k}$ ?
O...
A first order reaction is 25% complete in 30 minutes. Calculate the value of rate constant and t_{1/2}.
[ log 2 = 0.3010, log 4 = 0.6021, log 3 = 0.4771 ]
(a) The rate constant for a first order reaction is $40 \text{ s}^{-1}$. How much time will it take to reduce the initial concentration of the reactant to its $\frac{1}{10}$th value ? [log 10 = 1] OR (b) The reaction between A and B is first order with respect to A and zero order with respect to B. ...