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NEET2025ChemistryChemical KineticsActual

If the half-life ( t _ 1 / 2 ) for a first order reaction is 1 minutes, then the time required for 99.9 % completion of the reaction is closest to:

Options

  1. A2 minutes
  2. B4 minutes
  3. C5 minutes
  4. D10 minutes

Correct answer

D. 10 minutes

Step-by-step solution

For 1^ st order reactions : aligned t _ 99.90 % & =10 t _ 1 / 2 t _ 99.9 % & =10 1 & =10 minute aligned

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