NUCLEAR/ATOMIC PHYSICS PROJECT. Karen Porter-Davis. STEP-UP Summer Chamblee Charter High School

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1 NUCLEAR/ATOMIC PHYSICS PROJECT Karen Porter-Davis STEP-UP Summer 2013 Chamblee Charter High School This is project that focuses on different aspects of nuclear/atomic physics. I usually give the students about 2 months to complete the project, but that time line can be modified to fit the teacher s schedule. I also have the students work on it completely outside of class. SP2. Students will evaluate the significance of energy in understanding the structure of matter and the universe. a. Relate the energy produced through fission and fusion by stars as a driving force in the universe. b. Explain how the instability of radioactive isotopes results in spontaneous nuclear reactions.

2 NUCLEAR/ATOMIC PHYSICS PROJECT You must choose activity #5 and two other activities to complete this project. This activity will be due on and will count for a project, lab and quiz grade. You may work with up to three other people (no more than 4 people to a group) in any of my classes to complete this project, but you are all responsible for the material and the end product. All activities (except #5) require at least two quality documented references (not including your textbook) in proper form. For every day the project is late 15 pts will be deducted from the final grade. 1. (30 pts) Create a model or diagram of an ionizing smoke detector. Describe and label all of the parts of the smoke detector. Answer the following questions: 1) Why do ionizing smoke detectors contain an isotope that undergoes alpha decay rather than beta or gamma decay? 2) Explain how the alarm works and how the ions create an electric current in the detection chamber. 4. (30 pts) Create a report, model, poster, short video, or computer presentation that describes the nuclear reactions that take place in stars and how these reactions change during the life cycle of a star. 7. (30 pts) Bohr, Einstein, Planck, and Heisenberg each received the Nobel Prize for their contributions to 20 th century. Their lives were also affected by the events of WWII. Research their stories and the ways the war affected their work. What were their opinions about science and politics during and after the war? Write a report about your findings and your opinion regarding the involvement and responsibility of scientists in politics. 2. (30 pts) Create two opposing (pro and con) PSAs/brochures that discuss nuclear energy and nuclear power plants. 5. (40 pts) Complete the problems on the back of this sheet. 8. (30 pts) Investigate the problems that occurred to cause the Fukushima Daiichi nuclear disaster and what can be done to prevent another disaster. Also, give your substantiated opinion on whether this type of incident should lead to the demise of nuclear power. The presentation can be in the form of a report, poster, short video, or computer presentation. 3. (30 pts) Research how radioactive decay is used to date archaeological remains and fossils. What nuclear reactions are involved in the carbon- 14 dating technique? What assumptions are made when the carbon-14 dating technique is used? What time scale is the carbon-14 technique suitable for? Is the carbon- 14 technique appropriate to determine the age of a painting suspected to be 375 years old? How about dinosaur bones? Explain why or why not? Summarize your findings in a brochure or poster for visitors to a science/natural history museum. 6. (30 pts) Research the lives and careers of female nuclear physicists such as Marie Curie, Lise Meitner, Ida Tacke Noddack, and Maria Goeppert-Mayer. Create a presentation about one or all four of these scientists. Include a brief biography, the obstacles they had to overcome, their research and their legacy. The presentation can be in the form of a report, poster, short video, or PowerPoint. 9. (30 pts) Research the problem of nuclear waste in the United States. How much is there? What kinds of radioactive waste are there? Where are they produced? What are the costs and hazards associated with different techniques for disposal of radioactive waste? How do other countries deal with the problem? Choose the disposal option you think is most appropriate, and write a position paper. Include information about all options and the reasons for your choice.

3 NUCLEAR/ATOMIC PHYSICS PROJECT Name(s): Period: Date: Assignment Numbers: Assignment #5 (Required): Total Points: /40 pts Assignment # : Total Points: /30 pts Assignment # : Total Points: /30 pts Total Points: /100

4 NUCLEAR/ATOMIC PHYSICS PROJECT #5 ANSWER THESE ON A SEPARATE SHEET OF PAPER. For non-calculated questions you must provide your source (if from textbook just write text and the page #; for all others document in proper form) and for calculated problems you must show your work to earn full credit. 1) Oxygen has several isotopes. What do these isotopes have in common? How do they differ? 2) The protons in a nucleus repel one another with the Coulomb force. What holds these protons together? 3) Calculate the total binding energy of the following: (use atomic mass for the isotope not average atomic mass; put in units of MeV) a. 16 8O b Cr c Sn 4) Describe the symbol, composition, charge and effect on the parent nucleus of alpha, beta, and gamma radiation. 5) Complete the following radioactive decay formulas and identify which type of decay is occurring: a. 12 6C? + 0-1e + b Th? + 4 2He c.? Fr + 4 2He 6) The C-14 content decreases after the death of a living organism with a half-life of 5730 years. If an archaeologist finds a piece of wooden tool at a dig site and the C- 14 content of the tool is only 6.25% that of an equal carbon sample from a presentday tree, what is the age of the tool? 7) Explain how nuclear reactors utilize chain reactions. 8) A fission reaction leads to the formation of 141 Ba and 92 Kr when 235 U absorbs a neutron. a. How is this reaction expressed symbolically? b. How many neutrons are released in this reaction? 9) Name the four universal/fundamental interactions and the particles involved with each interaction. 10) What are quarks? Name the six flavors. 11) Describe leptons, hadrons, baryons and mesons. Give examples of each. 12) Describe the Big Bang Theory and how it relates to the universal/fundamental interactions.

5 NUCLEAR/ATOMIC PHYSICS PROJECT #5 TEACHER ANSWER SHEET 1) Oxygen has several isotopes. What do these isotopes have in common? How do they differ? They have the same number of protons and electrons; They have a different number of neutrons and therefore have a different number of nucleons. 2) The protons in a nucleus repel one another with the Coulomb force. What holds these protons together? The Strong Nuclear Force (Interaction) 3) Calculate the total binding energy of the following: (use atomic mass for the isotope not average atomic mass; put in units of MeV) Resting energy Equations: Since we are dealing with very small masses the atomic mass unit is commonly used and is defined so that 12 u = mass of 1 atom of C-12 Conversion factor 1 u = E -27 kg mass of a proton ~ 1 u E0 = mc 2 = [( E -27 kg)( E8 m/s 2 ) 2 ]/( E -19 J/eV) = MeV/u Binding Energy = (mass defect)(931.5 MeV/u) Ebind = m(931.5 MeV/u) m = Z(atomic mass of H) + N(mass of a neutron) atomic mass of isotope Z = atomic # Ham= u N = neutron # mn = u a. 16 8O m = 8( u) + 8( u) u = u Ebind = ( u)( MeV/u) = MeV or for partial credit: E -11 J or MeV/nucleon b Cr m = 24( u) + 28( u) u = u Ebind = ( u)( MeV/u) = MeV or for partial credit: E -11 J or MeV/nucleon c Sn m = 50( u) + 68( u) u = u Ebind = ( u)( MeV/u) = MeV or for partial credit:

6 E -10 J or MeV/nucleon 4) Describe the symbol, composition, charge and effect on the parent nucleus of alpha, beta, and gamma radiation. Type Symbol Composition Charge Effect on parent nucleus Alpha α ( 4 2He) 2 p + and 2 n 0 +2 Mass loss; new element produced Beta β - ( 0-1e) β + ( 0 +1e) Electron Positron No significant change in mass; new element produced Gamma Photon 0 Energy loss 5) Complete the following radioactive decay formulas and identify which type of decay is occurring: a. 12 6C? + 0-1e + Negative Beta decay; a neutron converts to a proton and electron; 12 7N b Th? + 4 2He Alpha decay; Ra Alpha decay; Ac c.? Fr + 4 2He 6) The C-14 content decreases after the death of a living organism with a half-life of 5730 years. If an archaeologist finds a piece of wooden tool at a dig site and the C-14 content of the tool is only 6.25% that of an equal carbon sample from a present-day tree, what is the age of the tool? 4 half lives x 5730 = 22, 920 years Number of Fraction Percentage half-lives remaining remaining elapsed 0 1 / / / / / / / /

7 7) Explain how nuclear reactors utilize chain reactions. The excess neutrons produced by each reaction are used to induce additional reactions. 8) A fission reaction leads to the formation of 141 Ba and 92 Kr when 235 U absorbs a neutron. a. How is this reaction expressed symbolically? 1 0n U 141 Ba + 92 Kr n b. How many neutrons are released in this reaction? 3 neutrons (a total of 236 n 0 (1 n ) ( ) = 3 9) Name the four universal/fundamental interactions and the particles involved with each interaction. Type of interaction Particles involved Strong Nuclear Gluon Weak Nuclear W or Z bosons Electromagnetism photon Gravity Graviton* this is not included in the standard model so the students could make an argument that there is not particle include 10) What are quarks? Name the six flavors. Quarks are elementary particles (cannot be broken down into smaller parts) and a fundamental constituent of matter. Six flavors: up, down, top, bottom, charm and strange (they have corresponding antiquarks) 11) Describe leptons, hadrons, baryons and mesons. Give examples of each. Particle type Description Examples Leptons In the weak, electromagnetic, and gravitational interactions; thought to be elementary particles Hadrons In the strong interaction; internal structure made of quarks Baryons Type of hadron; made up of 3 quarks Mesons Type of hadron; one quark and one anti-quark; very unstable Electrons, neutrinos, muon and tau leptons; corresponding antimatter antilepton 2 classes: baryons and mesons Protons: u,u,d Neutrons: u,d,d Pion: up, down anti Antipion: down, up anti 12) Describe the Big Bang Theory and how it relates to the universal/fundamental interactions. The universe erupted from a point like singularity about billion years ago. In the brief instant after the Big Bang came such extremes in the density of matter and energy that all 4 fundamental forces operated in a single unified way. The temperature and energy present reduced everything into an undifferentiated quark soup.

8 TEACHER GUIDE TO NUCLEAR PROJECT TOPIC # 1 Important parts of the Ionizing Smoke Detector: Ex) Ionization chamber (2 plates/electrodes with potential difference, radioactive source (Americium)) Voltage Source (battery) Alarm Current detector (electronics) Other parts: casing, LED, test switch, wiring, etc. Why do ionizing smoke detectors contain an isotope that undergoes alpha decay rather than beta or gamma? Alpha radiation cannot penetrate a sheet of paper and it is blocked by several centimeters of air (only dangerous if the americium is inhaled). How the alarm works and how the ions create an electric current in the ionization chamber: The Americium decays and generates alpha particles which ionize the Oxygen and Nitrogen atoms from the air in the ionization chamber. Ionization means that electrons are released from the atoms and they become positive ions. The electrons are negatively charged and are attracted to the positive plate and the positive ions are attracted to the negative plate. The electronics in the smoke detector sense the small amount of current that these electrons and positive ions moving toward the plates create. When smoke enters the ionization chamber, it disrupts this current because the smoke particles attach to the ions and neutralizes them. The smoke detector senses the drop in current between the plates and the alarm is set off.

9 TEACHER GUIDE TO NUCLEAR PROJECT TOPIC # 3 What nuclear reactions are involved in the carbon-14 technique? C-14 undergoes Beta decay to N C 14 7N + 0-1e + What assumptions are made when the carbon-14 dating technique is used? Carbon dating can only be used with organic materials (once living organisms: animals, plants, etc.) Is the carbon-14 technique appropriate to determine the age of a pointing suspected to be 375 years old? How about dinosaur bones? Carbon-14 has a half-life of ~ 5730 years and therefore works best for artifacts between 1000 and 25,000 years old.

10 NUCLEAR PHYSICS PROJECT #5 Name(s): Date: Period(s): 1) They have the same number of protons (1 pt) and electrons (0.5 pt); they have different number of neutrons (1 pt) and therefore have a different number of nucleons (extra 0.5 pt). Documented (0.5 pt) /3 2) The strong (1 pt) nuclear (0.5 pt) force. (if binding force: 0.75 pt) Documented (0.5 pt) 3) A) MeV (1 pt) ( E -11 J or MeV/nucleon) B) MeV (1 pt) ( E -11 J or MeV/nucleon) C) MeV (1 pt) ( E -10 J or MeV/nucleon) Work shown (0.75 pt: 0.25 pt for each) Correct units (MeV) (0.25 pt) /2 /4 4) A) Alpha: α (0.1 pt), 2p + and 2 n 0 (0.25 pt), +2 (0.25 pt), mass loss; new element produced (0.25 pt) B) Beta: β (0.1 pt), electron/positron (or a neutron p + and e - ) (0.25 pt), -1/+1 (0.25 pt), no significant change in mass; new element produced (0.25 pt) C) Gamma: (0.1 pt), photon (0.25 pt), 0 (0.25 pt), energy loss (0.25 pt) Documented (0.45 pt) /3 5) A) Beta decay (0.5 pt); (negative beta decay extra 0.5 pt); 12 7N (0.75 pt) B) Alpha decay (0.5 pt); Ra (0.75 pt) C) Alpha decay (0.5 pt); Ac (0.75 pt) Atomic masses and numbers included (0.25 pt) 6) 22,920 years (2 pts) Work shown (1 pt) /4 /3 7) The excess neutrons (1pt) produced by each reaction are used to induce additional reactions (1.5 pts). Documented (0.5 pt) /3 8) A) 1 0n U 141 Ba + 92 Kr n (0.5 pt for each part; total of 3 pt; include ) B) 3 neutrons (1 pt) /4 9) A) Strong (0.5 pt); gluon (0.4 pt) B) Weak (0.5 pt); W or Z (extra 0.25 pt) bosons (0.4 pt) C) Electromagnetism (0.5 pt); photon (0.4 pt)

11 D) Gravity (0.5 pt); Graviton (0.4 pt) * not included in standard model so the students could make an argument that there is not a particle included. Documented (0.4 pt) /4 10) Quarks are elementary particles (cannot be broken down into smaller parts) and a fundamental constituent of matter (1.5 pt) Flavors: up, down, top, bottom, charm, strange (1.5 pt; 0.25 pt each) The flavors have corresponding antiquarks (extra 0.5 pt) Documented (0.5 pt) /4 11) Particle type Description Examples Leptons Hadrons Baryons Mesons In the weak, electromagnetic, and gravitational interactions; thought to be elementary particles (0.5 pt) In the strong interaction; internal structure made of quarks (0.5 pt) Type of hadron; made up of 3 quarks (0.5 pt) Type of hadron; one quark and one antiquark; very unstable (0.5 pt) Electrons, neutrinos, muon and tau leptons; (0.4 pt)corresponding antimatter antilepton 2 classes: baryons and mesons (0.4 pt) Protons: u,u,d Neutrons: u,d,d (0.4 pt) Pion: up, down anti Antipion: down, up anti (0.4 pt) Documented (0.4 pt) /4 12) The universe erupted from a point like singularity about billion years ago. In the brief instant after the Big Bang came such extremes in the density of matter and energy that all four fundamental forces operated in a single unified way (1.5 pts). The temperature and energy present reduced everything into an undifferentiated quark soup (extra 0.5 pt). Documented (0.5 pt) /2 Total Points: /40 (with extra points up to 41.5) Comments: