Question

Tritium (half life =12.3 y) is used to verify the age of expensive brandies. If an old brandy contains 1/16 of the tritium present in the new brandy, then how long ago was it produced

Answer 1

Using radioactive decay and the half-life of tritium, which is 12.3 years, for a decrease to 1/16 of the original tritium amount, it takes four half-lives. Hence, the brandy was produced approximately 49.2 years ago.

To determine how long ago the brandy was produced using tritium dating, we employ the concept of radioactive decay and the half-life of tritium, which is 12.3 years. Since the tritium in the old brandy is 1/16 of that in the new brandy, we can use the half-life formula to find out the age. After each 12.3 years, the amount of tritium halves. Therefore, it takes four half-lives to go from the full amount to 1/16, as it halves to 1/2, then 1/4, then 1/8, and finally 1/16.

So, the calculation would be:

Age of brandy = Number of half-lives × Half-life of tritium

Age of brandy = 4 × 12.3 years

Age of brandy = 49.2 years

The old brandy was produced approximately 49.2 years ago.

Answer 2

59.2 years ago. Multiply 1/16 by 2s until you get one: 1/16*2*2*2*2. Every "2" or "*" represents a half life. In this case, there are 4 half lives. Do this: 4*12.3 and you get 59.2