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NEST2025ChemistryChemical Kinetics

Consider two radioactive substances P and Q that decay following a first order kinetics. It takes nine years for P for decay of 2 / 3^ rd of its initial amount. In the same nine years Q decays by half. If the ratio of the initial (t=0) amounts of P and Q , that is P ₀: Q ₀ is 81: 16 , the number of years after which the quantities of P and Q would be same is

Options

  1. A36
  2. B9
  3. C54
  4. D72

Correct answer

A. 36

Step-by-step solution

No Solution

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