Chemical Kinetics Test
Chemical Kinetics
This is chemical kinetics Test-04 for CBSE class 12 Chemistry.. There are 15 questions in this test with each question having around four answer choices.
Questions & Answers
1
Activation energy of a reaction is
- AThe minimum amount of energy required to overcome the barrierCorrect
- BThe energy absorbed during a reaction
- CThe energy released during the reaction
- DEnergy evolved when activated complex is formed
2
The rate law for the reaction is given by rate= k[RCl]. The rate for this reaction
- Ais halved by doubling the concentration of NaOH
- Bis halved by half by reducing the concentration of RClCorrect
- Cis doubled by doubling the concentration of NaOH
- Dis unaffected by change in temperature
3
For an endothermic reaction, the minimum value for the energy of activation in terms of will be
- AMore than $\Delta H$Correct
- BEqual to $\Delta H$
- CLess than $\Delta H$
- DZero
4
Order of the photochemical reaction occurring between hydrogen and chlorine is
- AZero orderCorrect
- BThird order
- CFirst order
- DSecond order
5
The temperature coefficient of most of the reactions lies between
- A1 and 3
- B2 and 4
- C2 and 3Correct
- D1 and 4
6
In a reaction 3A products, the concentration of A decreases from 0.6mol/L to 0.4mol/L in 5 mins. Calculate the rate during this interval
- A$\begin{array}{*{20}{l}} {2.22{\text{ }} \times {\text{ }}{{10}^{--{\text{ }}4}}mol{\text{ }}{L^{--{\text{ }}1}}{s^{--{\text{ }}1}}} \end{array}$Correct
- B$1.33{\text{ }} \times {\text{ }}{10^{--{\text{ }}2}}mol{\text{ }}{L^{--{\text{ }}1}}{s^--}$
- C$\begin{array}{*{20}{l}} {2{\text{ }} \times {\text{ }}{{10}^{--{\text{ }}2}}mol{\text{ }}{L^{--{\text{ }}1}}{s^{--{\text{ }}1}}} \end{array}$
- D$2.22{\text{ }}mol{\text{ }}{L^{--{\text{ }}1}}mi{n^{--{\text{ }}1}}$
7
For a chemical reaction $2X{\text{ }} + {\text{ }} \to Z$, the rate of disappearance of Z is 0.05$mol L^{– 1}min^ {– 1}$. The rate of disappearance of X will be
- A0.1$mol L^ {– 1}min ^{– 1}$Correct
- B$0.05mol{\text{ }}{L^{--{\text{ }}1}}mi{n^{--{\text{ }}1}}$
- C$\begin{array}{*{20}{l}} {0.25mol{\text{ }}{L^{--{\text{ }}1}}mi{n^{--{\text{ }}1}}} \end{array}$
- D0.05mol L – 1hour – 1
8
In the formation of sulphur trioxide ${\text{2S}}{{\text{O}}_{\text{2}}}{\text{(g) + }}{{\text{O}}_{\text{2}}}{\text{(g) }} \rightleftarrows {\text{ 2S}}{{\text{O}}_{\text{3}}}{\text{(g)}}$The rate of reaction is expressed as${\text{ - }}\frac{{{\text{d[O2]}}}}{{{\text{dt}}}} = 2.5X{10^{ - 4}}{\text{mol }}{{\text{L}}^{ - {\text{1}}}}{{\text{s}}^{ - {\text{1}}}}$The rate of disappearance of $SO_2$ will be
- A
- B
- CCorrect
- D
9
Following mechanism has been proposed for a reaction The rate law expression for the reaction is
- Ar = k[A][B]Correct
- Br = k[A]$^2$
- Cr = k[A]$^2$[B]
- Dr = k[A][C]
10
The expression which gives $3/{4^{th}}$ life of first order reaction is
- ACorrect
- B
- C
- D
11
If 75% of a first order reaction was completed in 32 min, then 50% of the reaction was completed in
- A24 min
- B8 min
- C16 minCorrect
- D4 min
12
Milk turns sour at 400C three times faster than it does at $0^o$C. this shows that activation energy of souring of milk ( in cal) is
- A
- B
- CCorrect
- D
13
Rate constant of a reaction is 0.0693 min – 1. Starting with 10 mol L – 1, the rate of reaction after 10 min will be
- A0.693 $ mol L ^{– 1}min^ {– 1} $
- B0.0693 $ mol L ^{– 1}min^ {– 1} $
- C0.1733 $ mol L ^{– 1}min^ {– 1} $
- D0.3465$ mol L ^{– 1}min^ {– 1} $Correct
14
In the presence of a catalyst, the activation energy of a reaction is lowered by 2 kcal at 27oC. the rate of reaction will increase by
- A28 timesCorrect
- B20 times
- C2 times
- D14 times
15
The half life of a reaction is halved as the initial concentration of the reactant is doubled. The order of the reaction is
- A3
- B2Correct
- C1
- D0