You attend a geology lab where you are asked to estimate the age of a fossil. The ratio of parent to daughter elements in the fossil sample is 1:7. You know that fossils are the remains of living organisms, which have some amount of C-14 isotope. The C-14 isotope, which has a half-life of 5730 years, begins to decay as the organism dies. What would be your estimation of the fossil's age?

17,190

Explanation:

The ratio of parent to daughter element in the sample of fossil is given by

1 : 7

Now we know that isotopes have half life. Half life of an isotopes is defined as the time taken to decay the quantity to half its starting quantity. After two half lives, the ratio of parent to daughter fossil sample become one - fourth and after three half lives the ratio becomes one - seventh.

When some organism dies, they don't take in any further carbon. The C-14 isotopes in the organisms decays after death in the organism and is not replaced again.

The C-14 isotope has a half life of 5730 years.

Thus in the context, it is given that ratio fossil elements in parent to daughter is 1 : 7 which forms after three half lives of C-14 isotopes.

Therefore, the estimated age of the fossil is 3 x 5730 = 17,190 years.