Question #72f8f

1 Answer
Jun 21, 2016

One sixteenth part.

Explanation:

Half life means that half of the number of atoms you start with has decayed (i.e. emitted radiation):

http://www.mathima.be/ftp/kernfysica/radioactief_verval.html

Iodine 131 has a half life of #8# days, so #32# days is four half lifes:

  • 1 half life = 1/2 left
  • 2 half lifes = 1/4 left
  • 3 half lifes = 1/8 left
  • 4 half lifes = 1/16 left

For more complex calculations you can use the equation:

#N(t) = N(0) * 0.5^(t/(T))#

In which #N(0)# is the number of atoms you start with, and #N(t)# the number of atoms left after a certain time #t# for a nuclide with a half life of #T#.