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प्रश्न
Which of the following graphs represents exothermic reaction?
(a)
(b)
(c)
विकल्प
(a) only
(b) only
(c) only
(a) and (b)
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उत्तर
(a) only
Explanation:
Exothermic reaction is a chemical reaction in which the enthalpy change is negative and energy is released in the form of light and heat.
As we all know, ΔH is negative.
Activation energy (forward reaction) – (backward reaction)
(Forward reaction) – Ea (backward reaction)
The product's exothermic energy exceeds the activation energy of the reactant.
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संबंधित प्रश्न
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`logk=logA-E_a/2.303R(1/T)`
Where Ea is the activation energy. When a graph is plotted for `logk Vs. 1/T` a straight line with a slope of −4250 K is obtained. Calculate ‘Ea’ for the reaction.(R = 8.314 JK−1 mol−1)
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| 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 |
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| (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 |
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