Tritium (³H) is used in glowing "EXIT" signs located where there is no electricity for lightbulbs.If the half-life of tritium is 12.26 years, what percentage of the original quantity of the isotope is left in the sign after 20.0 years?

Question

Quizplus · Accepted Answer

After 20 years, approximately 1.63 half-lives have passed (20/12.26). The remaining quantity is (1/2)^1.63 ≈ 0.323 or 32.3% of the original amount.

Tritium (3H) Is Used in Glowing "EXIT" Signs Located Where

Tritium (³H) Is Used in Glowing "EXIT" Signs Located Where