science

If the half life- period of a radioactive element is 1600.After how many years will if remains 25% of his quantity

  1. 8
asked by Prince
  1. 1600 what? If it isn't years, convert to years.
    k = 0.693/t1/2
    Substitute k into the below equation.
    ln(No/N) = kt
    No = 100
    N = 25
    k from above
    Solve for t in years.

    posted by DrBob222

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