Question 1
The age of an ancient tree trunk is estimated using radiocarbon dating. If the trunk has a C-14 decay rate that is 34% of what it is in living plants, how old is the trunk? The half-life of C-14 is 5730 years.
◦ 1.94 × 10
4 years
◦ 5.31 × 10
3 years
◦ 1.74 × 10
2 years
◦ 8.92 × 10
3 years
◦ 2.92 × 10
4 years
Question 2
The nuclide As-76 has a half-life of 26.0 hours. If a sample of As-76 weighs 344 g, what mass of As-76 remains after 538 minutes?
◦ 437 g
◦ 67.8 g
◦ 144 g
◦ 251 g
◦ 271 g