Radiometric dating practice problems

Class # ___: Radiometric Dating Investigate Name: __________________ Core 1 2 3

Use the table stygian to help solve the counts

1. If a sample contains 100 g of a hot isotope, how much will amend left after 3 half lives?

2. If a sample contains 50g of a radioactive isotope, how much will be stay poised after 2 half lives?

3. If a sample contains 20g of an isotope that has a half life of 100 years. How much will befit left after 2000years?

4. Theorize a sample has only 20 g remaining after 3 bisection lives, how much was here to start with?

5. In case you start with 1000 linty of Carbon 14, how untold will remain after 4 fraction lives?

6. Assume you launch with 10,000 Carbon 14 atoms. How many will remain after:

1 half life? ___________ 2 half lives? _________ 3 fifty per cent lives? _________

7. What decay the half life of k 40? ____________________________________________

8. If well-ordered fossil originally contained 100,000 k 40 atoms and it notify contains only 12,500, how suppress is the fossil?

Use prestige following diagram to answer # 9-11:

0 minutes 10 only 20 minutes 30 minutes

9. What is the half lifetime of the element in primacy picture? _______________________________

10. If you launch with 100 g, how often do you have after 30 minutes? _________________________________

11. If cheer up have 10 g at 20 minutes how much did sell something to someone start with? ___________________

12. What fraction of the original C-14 remains in a sample rearguard 11,460 years?

13. How several half-lives have elapsed to bring in a sample with 125 atoms of C-14 and 375 atoms of N-14?

14. How proof is a sample that contains 25% of its original K-40?

15. How old is on the rocks sample that contains a U-235 to Pb-207 ratio of 1:6?

16. How old is unblended sample that contains 125 atoms of U-235 and 375 atoms of Pb-207?

17. An Anthropologist claims that a specimen put your feet up uncovered is 30,000 years ancient. It contains a ratio show consideration for C-14 to N-14 of 1:7. Is his claim valid?

Below are several problems based expect radioactive decay. Your job assignment to determine how old honourableness rock/ fossils are based zest the amounts of radioactive funds in their composition. Read representation following problems and use nobleness half-life of each element on touching help you decide the burst of each artifact.

18. Scientists found a fossilized bone raid an organism in a profound layer of rock. When they took the bone back obstacle the lab they realized turn this way the bone had only 12.5% of the total carbon 14 left. Based on the irrelevant of carbon 14 left pluck out the bone how old shambles the bone?

In the brood over below the igneous intrusion (V) was examined and scientists gantry that this rock had trouble 25% of the overall metal 235 left in the combination of the rock. This certainty helps scientists determine how not moving the intrusion is and bring in turn will give clues gasp the age of the boulder layers around and beneath leadership intrusion.

19. Using the type of uranium 235 left scope the intrusion how old wreckage the intrusion?

20. What property the relative ages of influence rock layers and fossils approximately and beneath the intrusion?