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NEET2019ChemistryChemical KineticsActual

If the rate constant for a first order reaction is k , the time ( t ) required for the completion of 99 % of the reaction is given by

Options

  1. At = 0.693 / k
  2. Bt = 6.909 / k
  3. Ct = 4.606 / k
  4. Dt = 2.303 / k

Correct answer

C. t = 4.606 / k

Step-by-step solution

k = 2.303 t l o g a a - x a = 100 a - x = 100 - 99 = 1 k = 2.303 t l o g 100 1 t = 4 .606 k

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