Chemistry

Problem

An archaeologist wishes to estimate the age of an organic artefact using radioactive methods. a. (i) Define the term half-life of a radioactive isotope. b. (ii) Explain qualitatively how comparison of the present activity of

^{14}\text{C}

in the artefact with the activity in living matter permits an estimate of its age. c. (iii) Potassium-40 has a half-life of

1.25\times10^{9}\,\text{y}

whereas Carbon-14 has a half-life of

5.73\times10^{3}\,\text{y}

. Which of these isotopes is more suitable for dating (a) an Iron Age wooden tool believed to be

3000

years old, and (b) a volcanic rock believed to be

70

million years old? Give reason for each choice.

Browse the problem library