Find the correct relation when the activation energies of two reactions are
(Ea1 and Ea2, where Ea1 > Ea2, and the temperature of the reacting system is increased from (T1) to (T2).

1. K1'K1=K2'K2         

2. K1'K1>K2'K2

3. K1'K1<K2'K2         

4. K1'K1<2K2'K2

Subtopic:  Arrhenius Equation |
 55%
Level 3: 35%-60%
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The units of rate constant and rate of reaction are same for :
1. First order reaction
2. Second order reaction
3. Third order reaction
4. Zero order reaction

Subtopic:  Order, Molecularity and Mechanism |
 81%
Level 1: 80%+
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The plot of log k vs 1T helps to calculate : 

1. Energy of activation.
2. Rate constant of reaction.
3. Order of the reaction.
4. Energy of activation as well as the frequency factor.

Subtopic:  Arrhenius Equation |
 64%
Level 2: 60%+
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Which of the following represents the value of the pre-exponential factor (A) for a reaction when the rate constant is K = 1.2×103 mol–1 L s–1 and activation energy Ea = 2.0×102 kJ mol–1, in the limit \(T→∞\)?

1. 2.0 × 102 kJ mol–1
2. 1.2 × 103 mol–1L s–1
3. 1.2 × 103 mol L–1 s–1
4. 2.4 × 103 kJ mol–1L s–1

Subtopic:  Arrhenius Equation |
 82%
Level 1: 80%+
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The rate constant for a reaction 2×10–2 s–1 at 300 K and 8×10–2 s–1 at 340 K. The energy of activation of the reaction is:

1. 14.69 kJ mol–1

2. 29.39 kJ mol–1

3. 44.34 kJ mol–1

4. 22.05 kJ mol–1

Subtopic:  Arrhenius Equation |
 71%
Level 2: 60%+
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The reaction 2A + B + C  D + E is found to be a first-order reaction with respect to A, second-order reaction with respect to B, and zero-order reaction with respect to C. If the concentrations of A, B, and C are doubled, the rate of the reaction will be:

1. 72 times

2. 8 times

3. 24 times

4. 36 times

Subtopic:  Order, Molecularity and Mechanism |
 91%
Level 1: 80%+
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Forfirst-orderparallelreactionk1andk2are4and2min-1respectivelyat300K.IftheactivationenergiesfortheformationofBandCarerespectively30,000and38,314J/molrespectively.ThetemperatureatwhichBandCwillbeobtainedintheequimolarratiois:

               

1.  757.48 K

2.  378.74 K

3.  600.91 K

4.  None of the above 

Subtopic:  Arrhenius Equation |
 68%
Level 2: 60%+
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What is the temperature at which the rate constants of two reactions become equal, given that for reaction A → B,
k₁ = A₁ e (-Ea₁/RT) and for reaction X → Y, k₂ = A₂ e (-Ea₂/RT),
where A₁ = 108, A₂ = 1010, Ea₁ = 600 cal mol⁻¹, Ea₂ = 1800 cal mol⁻¹, and R = 2 cal K⁻¹ mol⁻¹?

1.  1600K

2.  1200x4.606K

3.  12004.606K

4.  6004.606K

Subtopic:  Arrhenius Equation |
 58%
Level 3: 35%-60%
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A reaction proceeds through several steps in a mechanism. The rate constants for the first, second, third, and fifth steps are k₁, k₂, k₃, and k₅, respectively.

The overall rate constant is given by:
k = (k₂ /k₃) x (k₁/ k₅ )¹ᐟ²

If the activation energies of these steps are 40 kJ mol⁻¹, 60 kJ mol⁻¹, 50 kJ mol⁻¹, and 10 kJ mol⁻¹, respectively.
What is the overall activation energy (in kJ mol⁻¹)?

 

1.  10

2.  20

3.  25
4. None of the above

Subtopic:  Arrhenius Equation |
 62%
Level 2: 60%+
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Considerthereaction.

               

Therateconstantfortwoparallelreactionswerefoundtobe10-2dm3mol-1s-1and4x10-2dm3mol-1s-1.Ifthecorrespondingenergiesofactivationoftheparallelreactionare100and120KJ/molrespecctively,thenetenergyofactivationEaofAis

1.  100 kJ/mol

2.  120 kJ/mol

3.  116 kJ/mol

4.  220 kJ/mol

Subtopic:  Arrhenius Equation |
 54%
Level 3: 35%-60%
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