Tritium has a half life of 12 5 years against beta decay What fraction of sample of pure tritium - Physics - Nuclei

Question

Tritium has a half life of 12 5 years against beta decay What
fraction of sample of pure tritium will remain undecayed after 25
years??

Hansraj Rai · Accepted Answer

As we know that, $T_{1 / 2} = \frac{0 693}{k} = 12 5 y r k = \frac{0 693}{12 5} = 0 05544$ Using the relation, $\ln (\frac{a_{0}}{a_{0} - x}) = k t \frac{a_{0}}{a_{0} - x} = {}_{e}{k t} = e^{0 05544 \times 25} \approx 4 \frac{a_{0} - x}{a_{0}} = \frac{1}{4} = 0 25$

Tritium has a half life of 12.5 years against beta decay .What fraction of sample of pure tritium will remain undecayed after 25 years??