Question

PLEASE HELP

A bone fragment has 10% of the parent Pb-210 remaining . The half-life of Pb -210 is 22 years . How old is the bone fragment ?

A. 73 years
B. 0.2 years
C. 75 years
D. 3.2 years

Answer 1

To find the age of the bone fragment, we can use the concept of half-life. The half-life of Pb-210 is given as 22 years, which means that after 22 years, half of the original amount of Pb-210 will decay.

Since the bone fragment has 10% of the parent Pb-210 remaining, we can conclude that it has gone through two half-lives, as 10% is one-eighth (1/8) of the original amount.

To calculate the age, we need to determine how many half-lives have passed. Since each half-life is 22 years, two half-lives would be 2 * 22 = 44 years. Therefore, the bone fragment is 44 years old.