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NEET2022ChemistryChemical KineticsActual

The half life of a first order reaction is 2000 years. If the concentration after 8000 years is 0.02 M , then the initial concentration was :

Options

  1. A0.16 M
  2. B0.32 M
  3. C0.08 M
  4. D0.04 M

Correct answer

B. 0.32 M

Step-by-step solution

Half life period (t_ 1 / 2 )=2000 years aligned k & = 0.693 2000 k & = 2.303 t [ A ]_o [ ~A ]_t 0.693 2000 & = 2.303 8000 [ A ]_o 0.02 [ A ]_o & =0.32 M aligned

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