The half life of H3 Tritium is 4 500 days If we had 12 grams

The half life of H-3 (Tritium) is 4, 500 days. If we had 12 grams to begin with, how much would there be after 13, 500 days? If we started with 120 g of Protoactinium-234, and had 1.88 g after 7 minutes, work out a value for its half life.

Solution

1. given half-life of H-3 tritium is 4500 days. that means in 4500 days its amount will reduce into half of the starting material.

So the amount of Tritium left after first 4500 days will be 6gm

the amount of tritium left after second 4500 days will be 3 gms

the amount of tritium left after last 4500 days will be 1.5 gms

2. if we start 120 gms of protactinium and had 1.88g after 7 minutes,

If we serially divide every number that we get after dividing 120 by 2 we will get a number of half life.

120, 60, 30, 15, 7.5, 3.75, 1.88

so it take 6 half life in seven minutes so the half life will be 7*60 / 6 =

70 seconds