Unit 4 Practice Exam

A) B)C) D)

1. Given the equation representing a nuclear reaction inwhich X represents a nuclide:

Which nuclide is represented by X?

A) absorb electrons B) absorb protonsC) decay D) oxidize

2. The nucleus of a radium-226 atom is unstable, whichcauses the nucleus to spontaneously

A) 1 B) 2 C) 0 D) 4

3. What is the mass number of an alpha particle?

A) B) C) D)

4. Which nuclear emission has the greatest mass?

A)B)C)D)

5. Which balanced equation represents a spontaneousradioactive decay?

A) the same charge and the same massB) the same charge and different massesC) different charges and the same massD) different charges and different masses

6. Positrons and beta particles have

A) nuclei of H-1 and H-2, onlyB) nuclei of H-1 and H-3 onlyC) nuclei of H-2 and H-3 onlyD) nuclei from H-1, H-2, and H-3

7. Radiation is spontaneously emitted from hydrogen-3nuclei, but radiation is not spontaneously emittedfrom hydrogen-1 nuclei or hydrogen-2 nuclei. Whichhydrogen nuclei are stable?

A) 3H B) 16N C) 19Ne D) 239Pu

8. Which radioisotope has an atom that emits a particlewith a mass number of 0 and a charge of +1?

A) an alpha particle B) a beta particleC) a neutron D) a proton

9. Which particle is emitted when an atom of 85Krspontaneously decays?

A) - B) + C) D) a

10. What is the decay mode of 37K?

A) It has a mass of 1 and a charge of 1.B) It has a mass of 0 and a charge of –1.C) It has a mass of 0 and a charge of 0.D) It has a mass of 4 and a charge of +2.

11. Which statement best describes gamma radiation?

A) alpha B) betaC) gamma D) positron

12. Which of these types of radiation has the greatestpenetrating power?

A) gamma B) neutronC) alpha D) beta

13. Which type of radiation has neither mass nor charge?

A) alpha particle B) beta particleC) positron D) gamma radiation

14. The diagram below represents radiation passingthrough an electric field.

Which type of emanation is represented by the arrowlabeled 2?

A) 14C B) 37Ca C) 53Fe D) 42K

15. Which radioisotope has the fastest rate of decay?

A) the same decay mode but different half-livesB) the same decay mode and the same half-lifeC) different decay modes and different

half-livesD) different decay modes but the same half-life

16. Which phrase describes the decay modes and thehalf-lives of K-37 and K-42?

A) 1/2 B) 1/4 C) 1/8 D) 1/16

17. A radioactive isotope has a half-life of 2.5 years.Which fraction of the original mass remainsunchanged after 10. years?

A) 3.0 h B) 9.6 h C) 12 h D) 24 h

18. After decaying for 48 hours, of the original massof a radioisotope sample remains unchanged. Whatis the half-life of this radioisotope?

A) Au-198 and N-16 B) Ca-37 and Fe-53C) I-131 and P-32 D) Tc-99 and U-233

19. Which radioisotopes have the same decay mode andhave half-lives greater than 1 hour?

A) combustion B) fermentationC) transmutation D) saponification

20. Which term represents a nuclear reaction?

A) combustion B) decompositionC) saponification D) transmutation

21. Given the balanced equation representing a reaction:

Which type of reaction is represented by thisequation?

A)B)C)D)

22. Which equation represents natural transmutation?

A)B)C)D)

23. Which nuclear equation represents a naturaltransmutation?

A) titration B) fissionC) electrolysis D) neutralization

24. In which process does a heavy nucleus split into twolighter nuclei?

A) redox reactionB) fission reactionC) substitution reactionD) neutralization reaction

25. The greatest amount of energy released per gram ofreactants occurs during a

A) The products are not radioactive.B) Stable isotopes are used as reactants.C) There is no chance of biological exposure.D) A large amount of energy is produced.

26. What is one benefit associated with a nuclear fissionreaction?

A) K-37, 1.24 h, B) N-16, 7.2 s, -

C) Rn-222, 1.6 x 103y, D) U-235, 7.1 x 108 y, -

27. Which nuclide is listed with its half-life and decaymode?

A) fission, mass converted to energyB) fission, energy converted to massC) fusion, mass converted to energyD) fusion, energy converted to mass

28. Given the balanced equation representing a nuclearreaction:

Which phrase identifies and describes this reaction?

A) addition B) fissionC) fusion D) substitution

29. A nuclear reaction in which two light nuclei combineto form a more massive nucleus is called

A) Matter is converted to energy.B) Energy is converted to matter.C) Ionic bonds are converted to covalent bonds.D) Covalent bonds are converted to ionic bonds.

30. Which change takes place in a nuclear fusionreaction?

A) B) C) D)

31. Given the fusion reaction:

Which particle is represented by X?

A) B) C) D)

32. Given the nuclear reaction:

What does X represent in this reaction?

A) B) C) D)

33. Given the correctly balanced nuclear equation:

Which particle is represented by the X?

A) alpha particle B) beta particleC) proton D) neutron

34. Given the nuclear reaction:

What is the identity of particle X?

A) charge B) energyC) isomers D) volume

35. During a nuclear reaction, mass is converted into

A) form heavy nuclides from light nuclidesB) form light nuclides from heavy nuclidesC) release a large amount of energyD) absorb a large amount of energy

36. A nuclear fission reaction and a nuclear fusionreaction are similar because both reactions

A) less than the mass of the reactants becausesome of the mass has been converted toenergy

B) less than the mass of the reactants becausesome of the energy has been converted to mass

C) more than the mass of the reactants becausesome of the mass has been converted to energy

D) more than the mass of the reactants becausesome of the energy has been converted to mass

37. In a nuclear fusion reaction, the mass of the productsis

A) Rn-222 B) I-131C) Co-60 D) C-14

38. The decay of which radioisotope can be used toestimate the age of the fossilized remains of aninsect?

A) Co-60 B) I-131C) C-14 D) U-238

39. Which radioisotope is used to treat thyroiddisorders?

A) acid rainB) helium gasC) greenhouse gases, such as CO2

D) radioisotopes with long half-lives

40. A serious risk factor associated with the operation ofa nuclear power plant is the production of

A) radon-222 B) radium-226C) cesium-137 D) cobalt-60

41. Refering to Table N, which substance is aradioactive waste product that is safest to releaseinto the atmosphere after it has decayed to a saferadiation level?

42. Base your answer to the following question on the information below and on your knowledge ofchemistry.

Nuclear fission reactions can produce different radioisotopes. One of these radioisotopes isTe-137, which has a half-life of 2.5 seconds. The diagram below represents one of the manynuclear fission reactions.

Complete the nuclear equation below for the beta decay of Zr-97, by writing an isotopic notation forthe missing product.

43. Base your answer to the following question on the information below

In living organisms, the ratio of the naturally occurring isotopes of carbon, C-12 to C-13 toC-14, is fairly consistent. When an organism such as a woolly mammoth died, it stopped taking incarbon, and the amount of C-14 present in the mammoth began to decrease. For example, onefossil of a woolly mammoth is found to have 1/32 of the amount of C-14 found in a livingorganism.

Determine the total time that has elapsed since this woolly mammoth died.

44. Base your answer to the following question on the information below.

A U-238 atom decays to a Pb-206 atom through a series of steps. Each point on the graph belowrepresents a nuclide and each arrow represents a nuclear decay mode.

Explain why the U-238 disintegration series ends with the nuclide Pb-206.

45. Base your answer to the following question on the information below and on your knowledge of chemistry.

Nuclear Waste Storage Plan for Yucca Mountain

In 1978, the U.S. Department of Energy began a study of Yucca Mountain which is located 90miles from Las Vegas, Nevada. The study was to determine if Yucca Mountain would be suitablefor a long-term burial site for high-level radioactive waste. A three-dimensional (3-D) computerscale model of the site was used to simulate the Yucca Mountain area. The computer model studyfor Yucca Mountain included such variables as: the possibility of earthquakes, predicted waterflow through the mountain, increased rainfall due to climate changes, radioactive leakage fromthe waste containers, and increased temperatures from the buried waste within the containers. The containers that will be used to store the radioactive waste are designed to last 10,000years. Within the 10,000-year time period, cesium and strontium, the most powerful radioactiveemitters, would have decayed. Other isotopes found in the waste would decay more slowly, butare not powerful radioactive emitters. In 1998, scientists discovered that the compressed volcanic ash making up Yucca Mountainwas full of cracks. Because of the arid climate, scientists assumed that rainwater would movethrough the cracks at a slow rate. However, when radioactive chlorine-36 was found in rocksamples at levels halfway through the mountain, it was clear that rainwater had moved quicklydown through Yucca Mountain. It was only 50 years earlier when this chlorine-36 isotope hadcontaminated rainwater during atmospheric testing of the atom bomb. Some opponents of the Yucca Mountain plan believe that the uncertainties related to the manyvariables of the computer model result in limited reliability of its predictions. However, advocatesof the plan believe it is safer to replace the numerous existing radioactive burial sites around theUnited States with the one site at Yucca Mountain. Other opponents of the plan believe thattransporting the radioactive waste to Yucca Mountain from the existing 131 burial sites creates toomuch danger to the United States. In 2002, after years of political debate, a final legislative voteapproved the development of Yucca Mountain to replace the existing 131 burial sites.

Why is water flow a crucial factor in deciding whether Yucca Mountain is a suitable burial site?

Answer Key(R) Unit 4 Practice Test

1. B2. C3. D4. A5. D6. C7. A8. C9. B10. B11. C12. C13. A14. D15. B16. C17. D18. C19. C20. C21. D22. B23. D24. B25. B26. D27. B28. C29. C30. A31. D32. B33. B34. A35. B36. C

37. A38. D39. B40. D41. A42.

43. 28 650 y44. – The nucleus of

Pb-206 is stable. –Pb-206 is notradioactive. – IfPb-206 were notstable, it wouldspontaneously decay.

45. Examples: – becausewater may transportthe radioactivematerials; – causecontainers to corrode