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MHT CET202124 Sep 2021Evening ShiftChemistryChemical KineticsActual

Half-life and rate constant for first order reaction are related by equation,

Options

  1. At_ 1 / 2 = k 0.693
  2. Bk = [ A ]₀-[ A ]_ t t _ 1 / 2
  3. Ct _ 1 / 2 = 0.693 k
  4. Dt _ 1 / 2 = [ A ]_ t -[ A ]₀ k

Correct answer

C. t _ 1 / 2 = 0.693 k

Step-by-step solution

For first order reaction, t = 2.303 k a ₀ a ₀- x At half-life, x=a₀ / 2 aligned & t = 2.303 k a ₀ a ₀- a ₀ 2 & t _ 1 / 2 = 2.303 k 2= 2.303 0.3010 k & t _ 1 / 2 = 0.693 k aligned

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