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Chemical Kinetics

Question
CBSEENCH12011335

The rate constant k1 and k2 for two different reactions are 1016. e-2000/T and 1015.e-1000/T respectively. The temperature at which k1 = k2

  • 1000 K 

  • 2000/2.303 K 

  • 2000 K 

  • 1000/2.303 K 

Solution

D.

1000/2.303 K 

The Arrhenius equation is represented as;
k = Ae-Ea/RT
In the given equations first, take log and then compare them.


k1 = 1016 e-2000/T
k2 = 1015 e-1000/T
On taking log, we get
log space straight k subscript 1 space equals space space log space space 10 to the power of 16 space minus fraction numerator 2000 over denominator 2.303 space end fraction straight T space... space left parenthesis straight i right parenthesis
log space straight k subscript 2 equals space log space 10 to the power of 15 space minus fraction numerator 1000 over denominator 2.303 end fraction space straight T......... space left parenthesis ii right parenthesis thin space

straight k subscript 1 space equals space straight k subscript 2
Hence comma space from space eqs space left parenthesis straight i right parenthesis space and space left parenthesis ii right parenthesis space
straight T space equals fraction numerator space 1000 over denominator 2.303 end fraction straight K space