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COMEDK2013ChemistryChemical Kinetics

A wooden box excavated from Indus valley had an activity of 1.18 10¹³ disintegration per minute per g of carbon. What is the approximate age of this civilisation?

Options

  1. A4000 years
  2. B5700 years
  3. C8100 years
  4. D6000 years

Correct answer

C. 8100 years

Step-by-step solution

aligned d N d t &= N d N d t &= 1 T 6.023 10²³ 12 T &= 6.023 10²³ 12 1.18 10¹³ d N d t =1.18 10¹³ &=42530 10⁶ ~min &= 4253 10⁶ 60 24 365 years = 1 T &=8092 years & 8100 years aligned

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