Name
Earth Systems
Radioactive Isotopes Review
Date
Period
Complete on a separate sheet of paper.
Define the following terms.
1. radioactivity
2. radioisotopes
3. radioactive decay
4. half-life
5. parent atom
6. daughter atom
7. radiometric dating
8. radiocarbon dating
Answer the following questions.
9. What are some examples of radioisotopes?
10. Why are atoms with atomic masses larger than 83 radioactive?
11. What are the types of radioactive decay?
12. Compare and contrast alpha and beta decay with gamma decay.
13. What is meant by parent atom and daughter atom in terms of radioactive decay?
14. Why are Earth scientists concerned with radioactive decay?
15. Compare and contrast radiometric dating with radiocarbon dating.
Solve the following problems.
16. How much of a 100.0g sample of 198Au is left after 8.10 days if its half-life is 2.70 days?
17. A 50.0g sample of 16N decays to 12.5g in 14.4 seconds. What is its half-life?
18. The half-life of 42K is 12.4 hours. How much of a 750 g sample is left after 62.0 hours?
Complete the following chart.
Time Passed
(years)
0
5,700
11,400
17,100
Mass of Parent Material
(g)
10
Mass of Daughter Material
(g)
Total Mass of Material
(g)
5
10
1.25
Use the graph to answer the following questions.
19. What is the half-life of Cesium-137?
20. How much mass is left after 5 half-lifes?
21. How many half-lifes have passed when there is 10g remaining?
Review from Chemistry Unit
1. Fill in the table with information on the characteristics of atomic parts
sub-atomic particle
location in atom
charge
Changing the
number of these
does what to the
atom?
number of neutrons
atomic mass
mass
electron
proton
neutron
2. Complete the following chart about the isotopes of carbon
isotope
number of protons
number of electrons
3. What does the term “valence” refer to in relation to atoms?
4. Compare and contrast homogeneous and heterogeneous mixtures.
5. Give three examples of each type of the above mixtures.
6. List two processes that result in chemical changes and explain why these are chemical.
7. List two processes that result in physical changes and explain why these are physical.
8. Fill in the following chart about phase changes:
process
condensing
freezing
deposition
sublimation
evaporation/boiling
melting
phase from
phase to
temperature
increasing or
decreasing?
chemical or physical
change?