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Chemical Kinetics

Question
CBSEENCH12006236

State and explain Arrehenius equation. How can we determine the activation energy of a reaction using this equation?

Solution
k=Ae-Ea/RT.

where k is rate constant, A is Arrhenius of frequency factor, Ea is energy of activation, T is absolute temperature. This equation is called Arrhenius equation.
Taking log, we get

        In k = In A - EaRT
2.303 log k = 2.303 log A - EaRT  log k = log A - Ea2.303 RT

Plot of log k versus 1 / T is a straight line with a negative slope. The slope of the line is equal to
 
   Slope = -Ea2.303R

          Ea = -slope × 2.303 × R