Tritium h) is an isotope of hydrogen that is sometimes used to make the hands of watches glow in the dark. the half-life of tritium is 123 years. if you start with 1 milligram of trition and wait 49 years, approximately how much of the original tritium remains? o a.6.25 ob.3.12% o c.25 o d. 506 o e 12.5%

Percentage of the isotope left is 75.87 %.

Explanation:

Initial mass of the isotope = 1 mg

Time taken by the sample, t =

Formula used :

where,

= initial mass of isotope

N = mass of the parent isotope left after the time, (t)

= half life of the isotope

= rate constant

Now put all the given values in this formula, we get

Percentage of the isotope left:

=

Percentage of the isotope left is 75.87 %.