Name: Class: Date: Chapter 4 Review 1. According to, all matter was made up of four elements: earth, air, fire, and water. 2. Unlike Democritus, Aristotle did not believe that matter was composed of tiny, indivisible. 3. John Dalton concluded that all the atoms of a single have the same mass. 4. The subatomic particle that J.J. Thomson discovered has a(an) charge. Figure 4-1 5. In Rutherford s gold foil experiment, shown in Figure 4-1, alpha particles that bounce straight back from the foil have struck in the gold atoms. 6. The results of Rutherford s gold foil experiment demonstrated that the occupies a very small amount of the total space inside an atom. 7. Protons and are found in the nucleus of an atom. 8. Neutrons and have almost the same mass. 9. If element Q has 11 protons, its atomic is 11. 10. The nuclei of isotopes contain different numbers of. 11. The of an isotope is the sum of the number of protons and neutrons in its nucleus. 12. In Bohr s model of the atom, move in fixed orbits around the nucleus. 13. When an atom gains or loses energy, some of its may move between energy levels. 14. The moving blades of an airplane propeller provide an analogy for the electron model. 15. The region in which an electron is most likely to be found is called a(an). 16. When all the electrons in an atom are in orbitals with the lowest possible energy, the atom is in its state. 1
17. An atom in which an electron has moved to a higher energy level is in a(an) state. 18. The difference between a sample of heavy water and regular water is that a hydrogen atom in heavy water has an extra. 19. The property of an element that indicates the number of protons in its atoms is the. 20. In an atom, the particles that have no charge are called. 21. What did Democritus believe about matter? 22. How did the results of J.J. Thomson s experiments change how scientists thought about atoms? 23. What did Rutherford conclude about the location of positive charge in an atom? 24. Which of the three subatomic particles proton, electron, or neutron has the least mass? 25. If an atom has 32 protons and 38 neutrons, what is its mass number? 26. If an atom of an element has a mass number of 31 and 16 neutrons in its nucleus, what is the atomic number of the element? 27. If an atom of germanium has a mass number of 70 and an atomic number of 32, how many neutrons are in its nucleus? 28. In the nucleus of an atom, there are 15 protons and 16 neutrons. What is the atomic number and mass number of this isotope? 2
29. How does the electron cloud model of the atom represent the locations of electrons in atoms? Atoms of Some Common Elements Substance Atomic Number Atomic Mass Protons Neutrons Electrons Sodium 11? 11 12? Magnesium 12 24 12? 12 Aluminum? 27 13 14 13 Phosphorus 15 31? 16 15 30. What is the atomic mass of sodium? 31. What is the total number of electrons in an atom of sodium? 32. How many neutrons are in an atom of magnesium? 33. The element silicon has been omitted from this table. It appears in the periodic table between aluminum and phosphorus, and in the same row. Given that information, which of the five columns could you fill in for silicon? 34. What is the atomic number of aluminum? 35. How many protons are in an atom of phosphorus? 3
36. A sample of calcium contains calcium-40, calcium-44, calcium-42, calcium-48, calcium-43, and calcium-46 atoms. Explain why these atoms can have different mass numbers, but they must have the same atomic number. 37. Explain what the colors in a fireworks display reveal about the movement of electrons in atoms. 38. Explain why the atoms of a particular element are exactly alike in some ways but may not be alike in other ways. Figure 4-2 39. In Figure 4-2, what is the main difference between the atomic model in panel 1 and the model in panel 2? 4
40. Are the atomic models in Figure 4-2 arranged in the order that they were developed? Explain your answer. 41. Draw the Bohr Model for Carbon and Chlorine. Be sure to include protons, neutrons and electrons. 5
ID: A Chapter 4 Review Answer Section COMPLETION 1. ANS: Aristotle PTS: 1 DIF: L1 OBJ: 4.1.1 2. ANS: atoms PTS: 1 DIF: L2 OBJ: 4.1.1 3. ANS: element PTS: 1 DIF: L1 OBJ: 4.1.2 4. ANS: negative PTS: 1 DIF: L1 OBJ: 4.1.3 5. ANS: nuclei PTS: 1 DIF: L2 OBJ: 4.1.3 6. ANS: nucleus PTS: 1 DIF: L2 OBJ: 4.1.3 7. ANS: neutrons PTS: 1 DIF: L1 OBJ: 4.2.1 8. ANS: protons PTS: 1 DIF: L2 OBJ: 4.2.1 9. ANS: number PTS: 1 DIF: L1 OBJ: 4.2.2 10. ANS: neutrons PTS: 1 DIF: L1 OBJ: 4.2.2 11. ANS: mass number 12. ANS: electrons PTS: 1 DIF: L1 OBJ: 4.3.1 13. ANS: electrons PTS: 1 DIF: L2 OBJ: 4.3.1 14. ANS: cloud PTS: 1 DIF: L1 OBJ: 4.3.2 1
ID: A 15. ANS: orbital PTS: 1 DIF: L2 OBJ: 4.3.2 16. ANS: ground PTS: 1 DIF: L1 OBJ: 4.3.3 17. ANS: excited PTS: 1 DIF: L2 OBJ: 4.3.3 18. ANS: neutron 19. ANS: atomic number PTS: 1 DIF: 2=Low/Mid OBJ: Physical Ch. 3.1.1 NOT: Physical Ch. 3.1.1 Describe the structure of an atom, and define protons, neutrons, and electrons. 20. ANS: neutrons PTS: 1 DIF: 3=Mid/High OBJ: Physical Ch. 3.1.1 NOT: Physical Ch. 3.1.1 Describe the structure of an atom, and define protons, neutrons, and electrons. SHORT ANSWER 21. ANS: Democritus believed all matter consisted of tiny particles that could not be divided into smaller particles. PTS: 1 DIF: L1 OBJ: 4.1.1 22. ANS: Scientists realized that atoms contained smaller subatomic particles. PTS: 1 DIF: L1 OBJ: 4.1.3 23. ANS: Rutherford concluded that positive charge was concentrated in the nucleus of an atom. PTS: 1 DIF: L1 OBJ: 4.1.3 24. ANS: electron PTS: 1 DIF: L1 OBJ: 4.2.1 25. ANS: 70 PTS: 1 DIF: L1 OBJ: 4.2.2 26. ANS: 15 2
ID: A 27. ANS: 38 28. ANS: atomic number = 15; mass number = 31 PTS: 1 DIF: L1 OBJ: 4.2.2 29. ANS: It provides a visual model of the most likely locations of electrons in an atom. PTS: 1 DIF: L2 OBJ: 4.3.2 30. ANS: 23 PTS: 1 DIF: 3=Mid/High OBJ: Physical Ch. 3.2.2 31. ANS: 11 PTS: 1 DIF: 2=Low/Mid OBJ: Physical Ch. 3.2.2 32. ANS: 12 PTS: 1 DIF: 3=Mid/High OBJ: Physical Ch. 3.2.2 33. ANS: Its atomic number is 14, and a silicon atom has 14 protons and 14 electrons. (You cannot figure out the number of neutrons or the atomic mass using this chart.) PTS: 1 DIF: 3=Mid/High OBJ: Physical Ch. 3.2.2 34. ANS: 13 PTS: 1 DIF: 2=Low/Mid OBJ: Physical Ch. 3.2.2 35. ANS: 15 PTS: 1 DIF: 2=Low/Mid OBJ: Physical Ch. 3.2.2 3
ID: A ESSAY 36. ANS: All the atoms of an element have the same atomic number because the atomic number equals the number of protons in an atom. If one of the atoms had a different number of protons, the atom would not be a calcium atom. The mass number can vary because it is the sum of the protons and neutrons and because isotopes of an element can have different numbers of neutrons. 37. ANS: When fireworks explode, the heat produced by the explosions causes some electrons in atoms to move to higher energy levels. When the electrons return to lower energy levels, some of the energy is released as visible light. The colors vary because each element has a different set of energy levels. PTS: 1 DIF: L2 OBJ: 4.3.3 38. ANS: All atoms of a particular element have the same number of protons and electrons. However, those atoms may have different numbers of neutrons. That means that the mass of individual atoms of an element may vary. PTS: 1 DIF: 2=Low/Mid OBJ: Physical Ch. 3.1.1 NOT: Physical Ch. 3.1.1 Describe the structure of an atom, and define protons, neutrons, and electrons. OTHER 39. ANS: Panel 1 depicts an atom as a solid sphere without any subatomic particles. Panel 2 shows an atom that has a subatomic structure. PTS: 1 DIF: L1 OBJ: 4.1.2 4.2.1 4.3.1 40. ANS: Yes; they go from the simplest (the solid sphere in 1) to the most complex (the electron cloud diagram in panel 3). Students may specifically cite John Dalton in connection with panel 1 and Niels Bohr in connection with panel 2 to support their answer. PTS: 1 DIF: L1 OBJ: 4.1.2 4.3.1 4.3.2 CASE 41. ANS: s PTS: 1 4