Question

Tritium with a half life of $12.5$ years undergoing beta decay what fraction of a sample of pure tritium will remain undecayed after 25 years.

• A. One half
• B. One fourth
• C. One third
• D. Can’t say

Answer 1

Answer: (B)

One fourth

Answer 2

: According to the concept of half life, half of the initial sample will remain un decayed after $12.55y.$ in next $12.5y,$ one half of these nuclei would decay. Hence one fourth of the initial sample of pure tritium will remain decayed.