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KVPY2011ChemistryChemical Kinetics

After 2 hours the amount of a certain radioactive substance reduces to 1 / 16^ th of the original amount (the decay process follows first-order kinetics). The half-life of the radioactive substance is

Options

  1. A15 ~min
  2. B30 ~min
  3. C45 ~min
  4. D60 ~min

Correct answer

B. 30 ~min

Step-by-step solution

0.693 t_ 1 / 2 = 2.303 2 60 a a / 16 t_ 1 / 2 =30 ~min

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