1. If an atom of ²⁴³Am emits an alpha particle, it becomes: (hint: use the periodic table).
a) ²³⁹Pa.
b) ²³⁹Np.
c) ²⁴¹Pa.
d) ²⁴¹Np.
e) ²³⁹Ac.

2. The radioactive isotope ⁴⁰K decays to the stable atom ⁴⁰Ar with a half-life of 1.3 billion years. If a rock has three times as much ⁴⁰Ar as ⁴⁰K, then the amount of time since the rock formed out of molten lava is:
a) 0.65 billion years.
b) 1.3 billion years.
c) 2.6 billion years.
d) 3.9 billion years.
e) 4.2 billion years.

3. ⁴⁰K radioactively decays to form ⁴⁰Ar. In addition to a neutrino, what other particle is emitted during this process? (hint: use the periodic table).
a) a positron.
b) an electron.
c) an alpha particle.
d) a lithium nucleus.
e) a carbon nucleus.

4. Fossils are generally found in which kind of rocks?
a) Sedimentary.
b) Igneous.
c) Metamorphic.
d) All three kinds equally.
e) Igneous and metamorphic equally.

5. Radioactive dating of a rock gives the age of:
a) igneous rocks since hardening.
b) sedimentary rocks since being cemented together.
c) metamorphic rocks since their transformation by large pressures.
d) metamorphic rocks since being cemented together.
e) all of the above.

6. In radioactive inverse beta decay (beta+ decay), which particle is produced?
a) an alpha particle.
b) an electron.
c) a gamma ray photon.
d) a positron.
e) a proton.

7. An alpha particle is:
a) a neutrino.
b) an electron.
c) a positron.
d) a hydrogen nucleus.
e) a helium nucleus.

8. Carbon-14 transforms via beta decay to:
a) Carbon-12.
b) Carbon-13.
c) Nitrogen-14.
d) Helium-4.
e) Boron-10.

9. The radioactive isotope ⁴⁰K decays to the stable atom ⁴⁰Ar with a half-life of 1.3 billion years. If a rock has the same amount of ⁴⁰Ar as ⁴⁰K, then the amount of time since the rock formed out of molten lava is:
a) 0.65 billion years.
b) 1.3 billion years.
c) 2.6 billion years.
d) 3.9 billion years.
e) 4.2 billion years.

10. By the time the Earth was 2.6 billion years old, there was significant oxygen in its atmosphere. This transformation of our atmosphere was likely caused by:
a) plants.
b) animals.
c) buffalo.
d cyanobacteria (blue-green algae).
e) volcanoes.

11. The half-life of carbon-14 is 5370 years. This means that:
a) All carbon-14 atoms decay 5370 years after they form.
b) Approximately half of the carbon-14 in a sample decays 5370 years after it is formed, and all of it is gone in 10740 years after it formed.
c) Approximately half of the carbon-14 in a sample decays 5370 years after it is formed, and 3/4th has decayed in 10740 years after it formed.
d) Approximately half of the carbon-14 in a sample decays 5370 years after it is formed, and 7/8th has decayed in 10740 years after it formed.
e) Approximately half of the carbon-14 in a sample decays 5370 years after it is formed; the rest is stable, and never decays.

12. Liquid metallic hydrogen is found:
a) in the interiors of all of the terrestrial planets.
b) in the interiors of all the Jovian planets.
c) in the interiors of Jupiter and Saturn.
d) underneath the ice of Europa, Ganymede, and maybe Enceladus.
e) on the surface of Titan.

13. Which process contributes the most to making Io volcanic?
a) Heat left over from its formation is seeping up from the center.
b) Meteoroids hitting Io crack the surface, causing liquid to flow onto the surface.
c) Tidal forces from Jupiter heat its interior.
d) Tidal forces from Saturn heat its interior.
e) Scientists have no idea why Io is volcanic.

14. Which of the following spacecraft dropped a probe into the atmosphere of Titan?
a) Global Surveyor.
b) Messenger.
c) Voyager 2.
d) New Horizons.
e) Cassini.

15. Which of the following moons has the most impact craters?
a) Callisto.
b) Europa.
c) Io.
d) Triton.
e) Titan.

16. The surface of Triton is:
a) a very cratered icy surface.
b) a rocky cratered surface, like the surface of Mercury and the highlands of the Moon.
c) in places similar in appearance to the surface of a cantalope.
d) extremely volcanic, with molten lava flowing from active volcanoes.
e) covered with water ice, with a possible ocean of liquid water underneath.

17. Which of the following objects is most likely to have a liquid water ocean under its surface?
a) Mars.
b) Io.
c) Europa.
d) Callisto.
e) Mercury.

18. Which of the following moons has the youngest surface?
a) The Moon.
b) Callisto.
c) Ganymede.
d) Europa.
e) Io.

19. The surface of Io has many:
a) tall volcanic mountains.
b) craters.
c) cracks in the ice.
d) lava flows.
e) dry river beds.

20. Which planet, dwarf planet, or moon is the New Horizons spacecraft targeting?
a) Mercury.
b) Venus.
c) The Moon.
d) Mars.
e) Pluto.

21. Which planet or Moon did the Magellan spacecraft map?
a) Mercury.
b) Venus.
c) Mars.
d) Jupiter.
e) Pluto.

22. Which planets have liquid metallic hydrogen in their interiors?
a) Only Jupiter.
b) Jupiter and Saturn only.
c) Neptune and Uranus only.
d) All of the Jovian planets.
e) Only the Earth and Venus.

23. The Jovian planets:
a) are gaseous throughout.
b) are mainly liquid, with thick atmospheres and a rocky core.
c) do not have solid cores: they are only liquid and gas.
d) are mostly solid, with a thick atmosphere but little liquid.
e) they are 99 percent gaseous, with a small rocky core.

24. Which of the following moons has the fewest craters?
a) Mimas.
b) Callisto.
c) The Earth's Moon.
d) Ganymede.
e) Io.

25. Which of the following spacecraft is in the process of making a radar map of Titan?
a) Messenger.
b) Global Surveyor.
c) Cassini.
d) New Horizons.
e) Magellan.

26. Which moons/planets have evidence for possible on-going volcanic/geyser activity?
a) Only Earth and Venus.
b) Only Earth and Io.
c) Earth, Mars, and Venus.
d) Earth, Io, Enceladus, and Triton.
e) Only Earth.

27. An atomic nucleus with two protons and two neutrons is sometimes called a/an:
a) gamma particle.
b) beta particle.
c) alpha particle.
d) hydrogen nucleus.
e) organelle.

28. Carbon-14 decays to Nitrogen-14 by emitting an anti-neutrino and a/an:
a) alpha particle.
b) proton.
c) positron.
d) electron.
e) gamma particle.

29. The radioactive isotope ¹⁴C decays to ¹⁴N with a half-life of 5370 years. If a shell has a ¹²C/¹⁴C ratio about twice that of the Earth's atmosphere, this shell has an approximate age of:
a) 5370/2 = 2685 years.
b) 5370 years.
c) 5370 X 2 = 10740 years.
d) 5370 X 3 = 16,110 years.
e) 5370 X 4 = 21,480 years.

30. A metamorphic rock:
a) is volcanic in origin.
b) is the best kind of rock for radioactive dating.
c) is another kind of rock that has been transformed by pressure and heat.
d) is chunks of other kinds of rocks, shell fragments, sand, etc., that have been cemented together.
e) the kind of rock that fossils are generally found in.

Answers: 1b, 2c, 3a, 4a, 5a, 6d, 7e, 8c, 9b, 10d, 11c, 12c, 13c, 14e, 15a, 16c, 17c, 18e, 19d, 20e, 21b, 22b, 23b, 24e, 25c, 26d, 27c, 28d, 29b, 30c.