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MHT CET202121 Sep 2021Morning ShiftChemistryChemical KineticsActual

In a first order reaction, concentration of reactant is reduced to (1 / 8)^ th of concentration in 23.03 minutes. What is half-life period of reaction?

Options

  1. A25 ~min
  2. B7.7 ~min
  3. C15 ~min
  4. D30 ~min

Correct answer

B. 7.7 ~min

Step-by-step solution

Initial concentration a ₀= a (let) Final concentration a_t= a 8 1^ st order reaction aligned & k = 2.303 t a ₀ a _ t = 2.303 23.03 a a / 8 & k = 1 10 8= 3 10 2=0.3 2 aligned Half -life t _ 1 / 2 = 2.303 2 k aligned & = 2.303 0.3 2 & =7.7 ~min aligned

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