Which is the correct relation between rate constant and half-life of a first-order reaction?

  • A
    $k \times t_{1/2} = 0.693$
  • B
    $t_{1/2} = \frac{k}{0.693}$
  • C
    $k \times t_{1/2} = \frac{1}{0.639}$
  • D
    $k \times 0.693 = t_{1/2}$

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