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Most Important Selected Qs for JEE AdvancedChemistryChemical Kinetics

Two radioactive nuclides X and Y have half lives of 100 min and 20 min respectively. In a sample, the ratio of nuclides of X : Y was found to be 1: 8 . Calculate the time after which the ratio of number of nuclides of X become twice that of Y .

Options

  1. A40 min
  2. B100 min
  3. C140 min
  4. D160 min

Correct answer

B. 100 min

Step-by-step solution

X ₀ 100 X ₀ 2 8 X ₀ 20 4 X ₀ 20 2 X ₀ 20 X ₀ 20 X ₀ 2 20 X ₀ 4 So, 8 X₀ 100 X₀ 4

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