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प्रश्न
Oxygen is available in plenty in air yet fuels do not burn by themselves at room temperature. Explain.
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उत्तर
The activation energy for combustion reactions of fuels is very high at room temperature therefore they do not burn by themselves.
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संबंधित प्रश्न
The rate constant for the first-order decomposition of H2O2 is given by the following equation:
`logk=14.2-(1.0xx10^4)/TK`
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(Given: R = 8.314 JK–1 mol–1)
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[R = 8.314 J K−1 mol−1]
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Activation energy of a chemical reaction can be determined by ______.
Consider figure and mark the correct option.
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(i) Rate of a reaction increases with increase in temperature.
(ii) Rate of a reaction increases with decrease in activation energy.
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(iv) Rate of reaction decreases with decrease in activation energy.
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(ii) Catalyst raises the activation energy.
(iii) Catalyst lowers the activation energy.
(iv) Catalyst alters enthalpy change of the reaction.
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In respect of the eqn k = \[\ce{Ae^{{-E_a}/{RT}}}\] in chemical kinetics, which one of the following statement is correct?
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.
A schematic plot of ln Keq versus inverse of temperature for a reaction is shown below
The reaction must be:
The rate of a reaction quadruples when temperature changes from 27°C to 57°C calculate the energy of activation.
(Given: R = 8. 314 J K−1 mol−1, log 4 = 0.6021)
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:
