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At 25^(@)C the activation energy for a c...

At `25^(@)C` the activation energy for a catalysed reaction is `126 KJ mol^(-1)` and for uncatalysed reaction is `350 KJ mol^(-1)` . How many times the rates is increased in the presence of catalyst ?

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According to Arrhenius equation , the specific rates (K) of reaction with different activation energies `(E_(a))` are given as .
`log (k_(1))/(k_(2)) = (1)/(2.303 RT) [ E_(a_(2)) - E_(a_(1))] = ((350-162)1000)/(2.303 xx 8.314 xx 298)`
Therefore the ratio of rates , `k_(1)//K_(2) = 8.9 xx 10^(32)`
In the presence fo a catalyst rate is increased by ` 8.9 xx 10^(32)` times .
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AAKASH SERIES-CHEMICAL KINETCS-EXERCISE - 3.2
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  3. Why the reactions involving covalent substances are slow? How they can...

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  6. What are reaction rate and specific rate? Write their units.

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  7. What is the role played by catalyst to alter the rate of reaction? Exp...

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  16. Discuss the energy barrier diagram for reaction rates. When the reacti...

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  17. The rate of a reaction triples when temperature changes from 20^(@)C t...

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  18. The rate constant at 0^(@)C is 7.87 xx 10^(-7)s^(-1) for a reaction wh...

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  20. In the chemical reaction, 3A + B to 2C + 3D, the rate of appearance o...

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