मराठी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

Activation energy of a chemical reaction can be determined by ______.

Advertisements
Advertisements

प्रश्न

Activation energy of a chemical reaction can be determined by ______.

पर्याय

  • determining the rate constant at standard temperature.

  • determining the rate constants at two temperatures.

  • determining probability of collision.

  • using catalyst.

MCQ
रिकाम्या जागा भरा
Advertisements

उत्तर

Activation energy of a chemical reaction can be determined by determining the rate constants at two temperatures.

Explanation:

`log  k_2/k_1 = E_a/(2.303R)(1/T_1 - 1/T_2)`

Where, Ea =  activation energy

T2 = higher temperature

T1 = lower temperature

k1 = rate constant at temperature T1

k2 = rate constant at temperature T2

This equation is known as Arrhenius equation.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 4: Chemical Kinetics - Exercises [पृष्ठ ४७]

APPEARS IN

एनसीईआरटी एक्झांप्लर Chemistry Exemplar [English] Class 12
पाठ 4 Chemical Kinetics
Exercises | Q I. 3. | पृष्ठ ४७

संबंधित प्रश्‍न

The rate constant of a first order reaction increases from 2 × 10−2 to 4 × 10−2 when the temperature changes from 300 K to 310 K. Calculate the energy of activation (Ea).

(log 2 = 0.301, log 3 = 0.4771, log 4 = 0.6021)


The rate constant for the decomposition of hydrocarbons is 2.418 × 10−5 s−1 at 546 K. If the energy of activation is 179.9 kJ/mol, what will be the value of pre-exponential factor?


In the Arrhenius equation for a first order reaction, the values of ‘A’ of ‘Ea’ are 4 × 1013 sec−1 and 98.6 kJ mol−1 respectively. At what temperature will its half life period be 10 minutes?

[R = 8.314 J K−1 mol−1]


The rate constant of a first order reaction are 0.58 S-1 at 313 K and 0.045 S-1 at 293 K. What is the energy of activation for the reaction?


The decomposition of a hydrocarbon has value of rate constant as 2.5×104s-1 At 27° what temperature would rate constant be 7.5×104 × 3 s-1if energy of activation is  19.147 × 103 J mol-1 ?


 Write a condition under which a bimolecular reaction is kinetically first order. Give an example of  such a reaction. (Given : log2 = 0.3010,log 3 = 0.4771, log5 = 0.6990).


 Predict the main product of the following reactions:


Which of the following graphs represents exothermic reaction?

(a)  

(b)  

(c)  


The reaction between \[\ce{H2(g)}\] and \[\ce{O2(g)}\] is highly feasible yet allowing the gases to stand at room temperature in the same vessel does not lead to the formation of water. Explain.


Thermodynamic feasibility of the reaction alone cannot decide the rate of the reaction. Explain with the help of one example.


Match the statements given in Column I and Column II

  Column I Column I
(i) Catalyst alters the rate of reaction (a) cannot be fraction or zero
(ii) Molecularity (b) proper orientation is not there always
(iii) Second half life of first order reaction (c) by lowering the activation energy
(iv) `e^((-E_a)/(RT)` (d) is same as the first
(v) Energetically favourable reactions (e) total probability is one are sometimes slow (e) total probability is one
(vi) Area under the Maxwell Boltzman curve is constant (f) refers to the fraction of molecules with energy equal to or greater than activation energy

What happens to most probable kinetic energy and the energy of activation with increase in temperature?


For an endothermic reaction energy of activation is Ea and enthalpy of reaction ΔH (both of there in KJ moI–1) minimum value of Ea will be ______.


Arrhenius equation can be represented graphically as follows:

The (i) intercept and (ii) slope of the graph are:


Explain how and why will the rate of reaction for a given reaction be affected when the temperature at which the reaction was taking place is decreased.


The decomposition of N2O into N2 and O2 in the presence of gaseous argon follows second-order kinetics, with k = (5.0 × 1011 L mol−1 s−1) `"e"^(-(29000  "K")/"T")`. Arrhenius parameters are ______ kJ mol−1.


Assertion (A): A reaction can have zero activation energy.

Reason (R): The minimum extra amount of energy absorbed by reactant molecules so that their energy becomes equal to the threshold value is called activation energy.

In the light of the above statements, choose the correct answer from the options given below:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×