Reactors & Nuclear Fuel Making Exam Click “next” to start the exam. Only one possible answer for each question. 1. Which of the following is the end product of the uranium mining and milling process?a. Uranium Tetraflouride (UF4)b. Uranium hexafluoride (UF6)c. Uranium oxide (U3O8)d. Uranium ore2. Uranium is produced by at least nineteen different countries around the world. Which three countries produce two-thirds of the world’s supply of uranium?a. USA, Russia, Kazakhstanb. Canada, Australia, Uzbekistanc. Kazakhstan, Canada, Australiad. Niger, Australia, Russia3. Which of the following methods of uranium recovery is most commonly used in the United States?a. In Situ Recovery (ISR)b. Conventional Miningc. Open pit miningd. Heap Leaching4. Which of the following is true about the conversion of uranium to hexafluoride (UF6)?a. It is a necessary step before the uranium can be enrichedb. It is necessary only when making fuel for heavy water reactorsc. It involves turning uranium gas into a solidd. None of the above5. What is the purpose of enrichment?a. To remove impurities from the uraniumb. To increase the proportion of fissile-prone U235 atomsc. To separate uranium from plutoniumd. To create MOX fuel6. Which of the following is NOT a method of uranium enrichment?a. Gaseous diffusionb. Electro-magnetic Isotope Separation (EMIS)c. Separation of Isotopes by Laser Excitation (SILEX)d. In Situ Recovery (ISR)7. Natural uranium primarily consists of two isotopes, only one of which is fissile. What is the isotopic make up of natural uranium?a. The isotope U-235 makes up 0.7% of natural uraniumb. The isotope U-238 makes up 0.7% of natural uraniumc. The isotope U-239 makes up 0.7% of natural uraniumd. None of the above8. Uranium is considered to be low enriched uranium (LEU) when it has an isotopic content of U235:a. Below 3%b. Below 10%c. Below 20%d. Below 50%9. Which of the following methods of enrichment uses magnets to separate the uranium isotopes U235 and U238?a. EMISb. SILEXc. Gaseous Diffusiond. Gas Centrifuge10. Which of the following explains why gas centrifuges are considered more of a proliferation risk than gaseous diffusion plants?a. They are more energy efficient and harder to detectb. They are much smaller and easier to hidec. They are cheaper to buildd. All of the above11. What is the significance for nonproliferation of the equilibrium time in gaseous diffusion and gas centrifuge methods of enrichment?a. The equilibrium time in gas centrifuges is measured in hours rather than months like gaseous diffusionb. The equilibrium time in gas centrifuges in measured in hours rather than weeks like gaseous diffusionc. The equilibrium time in gas centrifuges is measured in days rather than weeks like gaseous diffusiond. The equilibrium time in gas centrifuges is measured in weeks rather than years like gaseous diffusion12. What method of enrichment is based on the fact that different isotopes absorb different colors, or frequencies of light?a. EMISb. SILEXc. PUREXd. MOX13. What feature is common to all enriched uranium-fueled thermal neutron nuclear reactors but not fast neutron reactors?a. Moderatorb. Heavy Waterc. Coolantd. Light Water14. What types of nuclear reactors can use natural (un-enriched) uranium fuel?a. Light Waterb. High Temperature Gas Cooledc. Magnozd. CANDUe. C and D15. Which of the following materials can be used as a coolant in nuclear reactors?a. Carbon dioxideb. Liquid Sodiumc. Light Waterd. Heliume. All of the above16. Which of the following is NOT true about heavy water?a. It cannot be used as a moderator in reactors that can use natural uranium because it absorbs too many neutrons.b. It exists in regular water in small amountsc. Heavy water production in a country can indicate existence of a weapons programd. It contains hydrogen isotopes with one proton and one neutron17. What type of nuclear reactor can be refueled while on-line?a. CANDUb. LWRc. High Temperature Gas Cooledd. Liquid Metal Fast Breeder18. Why are reactors that can be fueled while on-line considered a greater proliferation risk than those that must be taken off-line?a. They are smaller and easier to hide, so can be used in covert weapons programsb. They only use enriched uranium for fuel, which can be diverted to make weaponsc. They don’t decrease their energy output while refueling, which makes it harder to detect any covert diversions of the spent fueld. They do not use enriched uranium for fuel, so don’t have any enrichment facilities that can be detected19. What happens at the end on the once-through fuel cycle?a. Spent fuel is removed from the reactor and stored permanentlyb. Spent fuel is removed from the reactor and is reprocessedc. MOX fuel is producedd. None of the above20. What is the reactor fuel produced from reprocessed plutonium and uranium called?a. Mixed oxide (MOX)b. Green saltc. Yellowcaked. Uranium hexafluoride (UF6)21. Which of the following is true about reprocessing?a. It is the cheapest commercial fuel cycle optionb. It is a necessary step in the fuel cycle for commercial reactorsc. It can only be done in large commercial facilitiesd. It can be used to recover plutonium for use in nuclear weapons22. PUREX refers to:a. A method of enrichment that uses lasers to separate isotopes of U235 from U238b. A type of fast breeder reactor that uses plutonium recovered from spent reactor fuelc. A method of separating uranium and plutonium from the fission products in spent reactor fueld. A step in the process for converting uranium ore into yellowcake23. Monitoring which of the following can serve as a nonproliferation tool?a. UF6 conversion facilitiesb. Production of heavy waterc. Electric or thermal output of nuclear reactors over timed. All of the above24. Which of the following is NOT a good reason for thinking that light water reactors (LWRs) are more proliferation resistant than graphite or heavy water moderated reactors?a. LWRs use LEU so access to enrichment facilities or enriched fuel is required and this generally is supplied from an out of country source.b. The quality of the plutonium in LWRs is so inferior to that produced in other reactors that it can’t be used to make efficient bombsc. Under normal operating procedures the plutonium produced in LWRs is irradiated longer, so it is more radioactive and harder to extract from the spent fueld. You have to shut down the reactor get at the plutonium in its spent fuel. Name Email Time is Up!