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Page 1 of 1 SC07B02 Unit 10 Exam Essays 287B15SP Questions 1–10: Answer the following questions. If necessary, use an equation program, such as that included in newer versions of Microsoft Word, to show your work. If you have questions about using Microsoft Word’s equation program, try searching the Microsoft Web site, located at http://office.microsoft.com/en-us/word/default.aspx. You can also use a program such as MathType to show your work with formulas, numbers, and units. You can download a free 30-day trial of MathType at http://www.dessci.com/en/products/mathtype/trial.asp. 1. According to the Bohr model, how many times larger is the orbit of hydrogen in the second level than in the first? 2. Calculate the radius of the innermost orbit of the hydrogen atom. Note that all factors in the equation are constants with the exception of n2. Find the radius of the orbit of the second, third, and fourth allowable energy levels in the hydrogen atom. 3. Calculate the energies of the first, second, third, and fourth energy levels in the hydrogen atom. 4. Calculate the energy difference between E3 and E2 in the hydrogen atom. Do the same for E4 and E3. 5. An isotope of oxygen has a mass number of 15. The atomic number of oxygen is 8. How many neutrons are in the nuclei of this isotope? 6. Three isotopes of uranium have mass numbers of 234, 235, and 238 respectively. The atomic number of uranium is 92. How many neutrons are in the nuclei of each of these isotopes? 7. How many neutrons are in an atom of the mercury isotope 200Hg80? 8. Write the symbols for the three isotopes of hydrogen with 0, 1, and 2 neutrons in the nucleus. 9. Write the nuclear equation for the transmutation of a radioactive uranium isotope, 234U92, into a thorium isotope, 230Th90, by the emission of an a particle. 10. Write the nuclear equation for the transmutation of a radioactive thorium isotope, 230Th90, into a radioactive radium isotope, 226Ra88, by the emission of an a particle.