Atomic Structure and Nuclear Chemistry Multiple Choice Questions PSI Chemistry Name: 1. What was the first particle discovered inside an atom? A. Proton C. Electron 2. What characteristic of cathode rays led scientists to believe that they were negatively charged? A. They were small B. They were easily deflected C. They were deflected towards a positive electrode D. They moved quickly 3. Millikan discovered the charge of this subatomic particle by calculating the charge of small oil droplets. A. Electron C. Proton 4. Of the three types of radioactivity characterized by Rutherford, which are particles? A. α-rays, β-rays, and γ-rays B. γ-rays C. α-rays and γ-rays D. α-rays and β-rays 5. Which form of radiation has a positive charge? A. α B. β C. γ D. δ 6. The gold foil experiment. A. confirmed the plum-pudding model of the atom
B. led to the discovery of the atomic nucleus C. was the basis for Thomson's model of the atom D. utilized the deflection of beta particles by gold foil 7. The nucleus of an atom does not contain. A. Subatomic particles B. protons or neutrons C. neutrons D. electrons 8. Which subatomic particle has the smallest mass? A. Proton C. Electron 9. Which subatomic particle has a positive charge? A. Proton C. Electron 10. The atomic number indicates. A. the number of neutrons in a nucleus B. the total number of neutrons and protons in a nucleus C. the number of protons in a neutral atom D. the number of atoms in 1 g of an element 11. In the symbol, x 6C, x is. A. the number of neutrons B. the atomic number C. the mass number D. the isotope number 12. There are electrons, protons, and neutrons in an atom of 133 55 Cs. A. 132, 132, 54 B. 54, 54, 132 C. 78, 78, 54 D. 55, 55, 78
13. How many electrons are in an Iron atom? A. 23 B. 26 C. 27 D. 28 14. In balancing the nuclear reaction 238 92U 234 90E + 4 2He, the identity of element E is. A. Pu B. Np C. Th D. Pa 15. This reaction 210 84Po 206 82Pb + is an example of. A. alpha decay B. beta emission C. gamma emission D. positron emission 16. The missing product from this reaction is. 121 53I 121 52Te + A. 4 2He B. 0-1e C. 1 0n D. 0 1e 17. This reaction is an example of. 41 20Ca 41 19K + A. alpha decay B. beta decay C. positron decay D. electron capture 18. Which isotope has 45 neutrons? A. 80 36Kr B. 80 35Br C. 78 34Se D. 34 17Cl 19. Bombardment of uranium-235 with a neutron generates tellurium-135, 3 neutrons, and. A. zirconium-98.
B. krypton-101. C. krypton-103. D. strontium-99. 20. The reaction shown below is responsible for creating 14 C in the atmosphere. What is the bombarding particle? 14 7N + 14 6C + 1 1H A. alpha particle B. electron C. neutron D. positron 21. What happens to the mass number and the atomic number of an element when it undergoes beta decay? A. Neither the mass number nor the atomic number change. B. The mass number decreases by 4 and the atomic number decreases by 2. C. The mass number does not change and the atomic number increases by 1. D. The mass number does not change and the atomic number decreases by 2. 22. Which one of the following is a correct representation of a beta particle? A. 4 2e B. 1 0β C. 0-1e D. 2 4β 23. Which one of the following processes results in an increase in the atomic number? A. gamma emission B. positron emission C. beta emission D. alpha emission 24. Of the following processes, which one changes the atomic number? A. alpha emission B. beta emission C. electron capture D. positron emission 25. In what type of radioactive decay does the atomic number of the product increase by one? A. alpha B. beta C. gamma D. positron emission
26. Which type of radioactive decay results in no change in mass number and atomic number for the starting nucleus? A. alpha B. beta C. positron emission D. gamma ray 27. What happens to the mass number and the atomic number of an element when it emits alpha radiation? A. The mass number remains unchanged while the atomic number decreases by one. B. The mass number decreases by four and the atomic number decreases by two. C. The mass number increases by four and the atomic number increases by two. D. The mass number remains unchanged while the atomic number increases by one. 28. Different isotopes of a particular element contain the same number of. A. protons B. neutrons C. protons and neutrons D. subatomic particles 29. Element X has three naturally occurring isotopes. The masses (amu) and % abundances of the isotopes are given in the table below. The average atomic mass of the element is amu. i. Isotope % Mass ii. 40 X 13.01 40.10 iii. 41 X 6.98 41.00 iv. 44 X 79.99 43.98 A. 43.26 B. 39.68 C. 39.07 D. 38.64 30. The beta decay of cesium-137 has a half-life of 30.0 years. How many years must pass to reduce a 25 mg sample of cesium-137 to 8.7 mg? A. 46 B. 32 C. 3.2 D. 52
31. The half-life for beta decay of strontium-90 is 28.8 years. A milk sample is found to contain 10.3 ppm strontium-90. How many years would pass before the strontium-90 concentration would drop to 1.0 ppm? A. 92.3 B. 0.112 C. 186 D. 96.9 32. The half-life of 131 I is 0.220 years. How much of a 500.0 mg sample remains after 24 hours? A. 496 mg B. 560 mg C. 219 mg D. 405 mg
ANSWER KEY 1. C 2. C 3. A 4. D 5. A 6. B 7. D 8. C 9. A 10. C 11. C 12. D 13. B 14. C 15. A 16. D 17. C 18. B 19. A 20. D 21. C 22. C 23. C 24. B 25. B 26. D 27. B 28. A 29. A 30. D 31. D 32. B