Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

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volcano sample test Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Volcanic belts form along a. islands in the Pacific Ocean. b. North American mountain ranges. c. the boundaries of Earth s plates. d. the coast of Antarctica. 2. The formation of the Hawaiian Islands is one example of a. volcanoes forming over a hot spot. b. volcanoes forming along plate boundaries. c. the Ring of Fire. d. continental drift. 3. The viscosity of magma depends upon its silica content and its a. pahoehoe. b. temperature. c. magnetism. d. pyroclastic flow. 4. The long tube in the ground that connects the magma chamber to Earth s surface is called the a. vent. b. side vent. c. pipe. d. crater. 5. If a volcano s magma is high in silica, the volcano will probably a. erupt quietly. b. remain dormant. c. erupt explosively. d. produce dark-colored lava. 6. Pahoehoe is a. cooler, slower-moving lava. b. fast-moving, hot lava. c. volcanic ash. d. lava with a rough, chunky surface. 7. When groundwater heated by magma rises to the surface and collects in a natural pool, it is called a a. hot spring. b. geyser. c. vent. d. pyroclastic flow. 8. In volcanic areas, groundwater heated by magma is a source of a. lava flows. b. silica. c. geothermal energy. d. pyroclastic flows. 9. Which of the following volcano hazards is made up of rocky particles about the size of a grain of sand? a. volcanic bombs b. pahoehoe

c. volcanic cinders d. volcanic ash 10. The main hazard from a quiet volcanic eruption is a. volcanic gases. b. lava flows. c. geysers. d. pyroclastic flows. 11. Tall, cone-shaped mountains in which layers of lava alternate with layers of ash are called a. shield volcanoes. b. cinder cone volcanoes. c. composite volcanoes. d. lava plateaus. 12. When many layers of thin, runny lava build up a high, level area, the result is a a. lava plateau. b. shield volcano. c. cinder cone volcano. d. composite volcano. 13. Which type of rock would you expect to form as the result of an explosive eruption? a. pahoehoe b. granite c. pumice d. aa 14. What is the landform that forms when a mass of hardened magma is uplifted, causing the layers of rock to bend upward? a. volcanic neck b. dike c. lava plateau d. dome mountain 15. The major ingredient of magma is a. pahoehoe. b. silica. c. dissolved gases. d. obsidian. 16. What can be used to identify a substance or to predict how it will behave? a. stages of activity b. physical and chemical properties c. geothermal activity d. viscosity 17. What triggers the small earthquakes that occur around a volcano before an eruption? a. upward movement of magma b. pyroclastic flow c. cooling magma inside the crust d. plate movements 18. All of the following are examples of physical properties EXCEPT a. melting point. b. hardness. c. ability to burn. d. density. 19. Before lava reaches the surface, the molten material is called

a. rock. b. magma. c. volcanic ash. d. liquid fire. 20. The volcanoes along converging oceanic plate boundaries may form a. a hot spot. b. a part of the mid-ocean ridge. c. an island arc. d. a subducting plate. 21. A mass of rock formed when a large body of magma cools inside the crust is called a a. neck. b. dike. c. lava plateau. d. batholith. 22. A volcano that may erupt again at some time in the distant future is a. active. b. dormant. c. explosive. d. extinct. 23. The huge hole left by the collapse of a volcanic mountain is called a a. lava plateau. b. caldera. c. cinder cone. d. shield volcano. 24. If geologists detect many small earthquakes in the area near a volcano, what can they infer about the volcano? a. It is dormant. b. It is probably about to erupt. c. It is extinct. d. It is a good source of geothermal energy. 25. Several kilometers from a volcano, a geologist observes an old lava flow made up of dark-colored basalt rock. The geologist infers that the lava must have had a. high silica content. b. high viscosity. c. low viscosity. d. medium viscosity. 26. When ash, cinders, and bombs build up in a steep pile around a volcano s vent, the result is a a. cinder cone volcano. b. shield volcano. c. composite volcano. d. dormant volcano. 27. When magma hardens in a volcano s pipe, the result will eventually be a landform called a a. batholith. b. dike. c. volcanic neck. d. sill. 28. Magma that forces across rock layers hardens into a a. sill. b. volcanic neck. c. dike.

d. batholith. 29. What provides the force that causes magma to erupt to the surface? a. the silica in the magma b. dissolved gases trapped in the magma c. gravity in the lithosphere d. the density of the magma 30. Which of the following helps to determine how easily magma flows? a. the amount of silica in the magma b. the diameter of the pipe c. the size of the crater d. the number of vents on the volcano Modified True/False Indicate whether the sentence or statement is true or false. If false, change the identified word or phrase to make the sentence or statement true. 31. Viscosity increases as temperature increases. _ 32. A dike forms when magma forces itself between rock layers and hardens. _ 33. Ash, cinders, and bombs build up in a steep pile to form cinder cone volcanoes. _ 34. Volcanoes that form along a mid-ocean ridge occur at a(n) diverging plate boundary. _ 35. Dissolved minerals trapped in magma under tremendous pressure provide the force for a volcanic eruption. _ 36. A pyroclastic flow typically occurs during a(n) quiet eruption. _ 37. A(n) dormant volcano is erupting or may erupt in the near future. _ 38. Magma sometimes forces its way out of the side of a volcano through a(n) vent. _ 39. During a quiet eruption, a(n) lava flow may set fire to and then bury everything in its path. _ 40. The greater the viscosity of a liquid, the slower it flows. _ Completion Complete each sentence or statement. 41. A(n) is a substance that cannot be broken down into other substances. 42. A substance made of two or more elements that have been chemically combined is a(n). 43. A mass of rock that forms when a large body of magma cools inside the crust is called a(n). 44. Hardened magma in a volcano s pipe that remains when softer rock around it has worn away is called a(n) _.

45. A huge hole, or, is left when the roof of a volcanic mountain s magma chamber collapses. 46. A major volcanic belt known as the _ circles the Pacific Ocean. 47. A liquid with little among its particles will have low viscosity. 48. A(n) is an area where material from deep within the mantle rises and then melts, forming magma. 49. A quiet eruption may produce slow moving, cooler lava that hardens to form rough chunks. This type of lava is called. 50. Groundwater heated by a nearby body of magma can spray from the ground under pressure, forming a(n). 51. Mountains that are formed by volcanoes along a coastline occur at a(n) plate boundary. 52. An energy source called energy is provided by water heated by magma. 53. A string of islands known as a(n) can form from the collision of two oceanic plates. 54. The resistance of a liquid to flowing is called. 55. Molten material that leaves a volcano s vent is called. 56. Magma flows easily when it is low in, a material made of oxygen and silicon. 57. The bowl-shaped area around a volcano s central vent is called a(n). 58. Sometimes rising magma is blocked by horizontal layers of rock. The magma forces the layers of rock to bend upward into a landform called a(n) _. 59. The smallest lava fragments produced by an explosive eruption are called volcanic. 60. An eruption of ash, cinders, bombs, and gases from a volcano is called a(n) _. Short Answer Use the diagram to answer each question. 61. Name the type of volcano illustrated in diagram A and describe how it forms.

62. Name the type of volcano illustrated in diagram B and describe how it forms. 63. Name the type of volcano illustrated in diagram C and describe how it forms. 64. In the United States, where do volcanoes like the one shown in diagram C occur? 65. What kind of eruption quiet, explosive, or both at different times would you expect from each volcano shown? 66. If the magma chamber beneath volcano B empties and then collapses, what kind of feature will form? Explain. Use the diagram to answer each question. 67. How do volcanoes form at B? 68. In the United States, where can volcanoes like those at B be found? 69. Describe an exception to the patterns pictured at A and B where volcanoes also can form. 70. Name and describe the type of boundary shown at A. 71. How do volcanoes form at A? 72. Name and describe the type of boundary shown at B. Essay 73. How does the release of trapped gases in magma cause a volcano to erupt? 74. You live on a large volcanic island not far from an active volcano. Besides damage from lava, what other hazards might affect your town and its people? 75. What kind of volcanic activity might you expect to observe at or near a dormant volcano? 76. What kind of eruption is likely to occur in a volcano having magma that is low in silica? Explain your answer. 77. Compare and contrast lava plateaus and dome mountains.

78. What is the difference between the physical and chemical properties of a substance? 79. Describe the three stages of a volcano. 80. Why do different liquids have different viscosities?

volcano sample test Answer Section MULTIPLE CHOICE 1. ANS: C DIF: L1 REF: p. F-83 OBJ: F.3.1.1 2. ANS: A DIF: L2 REF: p. F-85 OBJ: F.3.1.2, 5.1.B.3, 5.1.A.2 3. ANS: B DIF: L1 REF: p. F-89 OBJ: F.3.2.3 STO: 5.1.B.3, 5.6.A.2 4. ANS: C DIF: L1 REF: p. F-92 OBJ: F.3.3.1 5. ANS: C DIF: L1 REF: p. F-94 OBJ: F.3.3.2 STO: 5.1.B.3, 5.6.A.2 6. ANS: B DIF: L1 REF: p. F-90 OBJ: F.3.2.3 STO: 5.6.A.2, 5.1.B.3 7. ANS: A DIF: L2 REF: p. F-104 OBJ: F.3.4.3, 5.7.B.3 8. ANS: C DIF: L2 REF: p. F-105 OBJ: F.3.4.3 STO: 5.7.B.3 9. ANS: D DIF: L3 REF: p. F-96 OBJ: F.3.3.2 STO: 5.2.B.1 10. ANS: B DIF: L3 REF: p. F-94 OBJ: F.3.3.2 STO: 5.1.B.3, 5.6.A.2 11. ANS: C DIF: L1 REF: p. F-101 OBJ: F.3.4.1 12. ANS: A DIF: L2 REF: p. F-101 OBJ: F.3.4.1 13. ANS: C DIF: L2 REF: p. F-94, p. F-95 OBJ: F.3.3.2 STO: 5.1.B.3, 5.6.A.2, 5.8.C.1 14. ANS: D DIF: L2 REF: p. F-104 OBJ: F.3.4.2, 5.7.B.3 15. ANS: B DIF: L1 REF: p. F-89 OBJ: F.3.2.3 STO: 5.1.B.3, 5.6.A.2 16. ANS: B DIF: L2 REF: p. F-87 OBJ: F.3.2.1 STO: 5.6.A.2, 5.6.A.3, 5.1.A.3 17. ANS: A DIF: L3 REF: p. F-98 OBJ: F.3.3.3 STO: 5.2.A.2, 5.8.C.1 18. ANS: C DIF: L2 REF: p. F-88 OBJ: F.3.2.1 STO: 5.6.B.1, 5.6.A.2 19. ANS: B DIF: L2 REF: p. F-82 OBJ: F.3.1.1, 5.1.B.1 20. ANS: C DIF: L2 REF: p. F-84 OBJ: F.3.1.1 21. ANS: D DIF: L1 REF: p. F-104 OBJ: F.3.4.2, 5.7.B.3 22. ANS: B DIF: L1 REF: p. F-97 OBJ: F.3.3.3

, 5.2.B.1 23. ANS: B DIF: L1 REF: p. F-102 OBJ: F.3.4.1 24. ANS: B DIF: L2 REF: p. F-98 OBJ: F.3.3.3 STO: 5.2.A.2, 5.8.C.1 25. ANS: C DIF: L3 REF: p. F-89 OBJ: F.3.2.3 STO: 5.1.B.3, 5.6.A.2 26. ANS: A DIF: L2 REF: p. F-100 OBJ: F.3.4.1 27. ANS: C DIF: L1 REF: p. F-103 OBJ: F.3.4.2 28. ANS: C DIF: L1 REF: p. F-103 OBJ: F.3.4.2 29. ANS: B DIF: L3 REF: p. F-92, p. F-93 OBJ: F.3.3.1 30. ANS: A DIF: L2 REF: p. F-89 OBJ: F.3.2.3 STO: 5.1.B.3, 5.6.A.2 MODIFIED TRUE/FALSE 31. ANS: F, decreases DIF: L2 REF: p. F-90 OBJ: F.3.2.2 STO: 5.6.A.2, 5.1.B.3 32. ANS: F, sill DIF: L2 REF: p. F-103 OBJ: F.3.4.2 33. ANS: T DIF: L2 REF: p. F-100 OBJ: F.3.4.1 34. ANS: T DIF: L1 REF: p. F-83 OBJ: F.3.1.1 35. ANS: F, gases DIF: L2 REF: p. F-92, p. F-93 OBJ: F.3.3.1 36. ANS: F, explosive DIF: L1 REF: p. F-95 OBJ: F.3.3.1 37. ANS: F, active DIF: L1 REF: p. F-97 OBJ: F.3.3.3, 5.2.B.1 38. ANS: T DIF: L2 REF: p. F-92 OBJ: F.3.3.1 39. ANS: T DIF: L3 REF: p. F-94 OBJ: F.3.3.2 STO: 5.1.B.3, 5.6.A.2 40. ANS: T DIF: L1 REF: p. F-88 OBJ: F.3.2.2 STO: 5.6.B.1, 5.6.A.2 COMPLETION

41. ANS: element DIF: L1 REF: p. F-87 OBJ: F.3.2.1 STO: 5.6.A.2, 5.6.A.3, 5.1.A.3 42. ANS: compound DIF: L1 REF: p. F-87 OBJ: F.3.2.1 STO: 5.6.A.2, 5.6.A.3, 5.1.A.3 43. ANS: batholith DIF: L1 REF: p. F-104 OBJ: F.3.4.2, 5.7.B.3 44. ANS: volcanic neck DIF: L2 REF: p. F-103 OBJ: F.3.4.2 45. ANS: caldera DIF: L1 REF: p. F-102 OBJ: F.3.4.1 46. ANS: Ring of Fire DIF: L1 REF: p. F-83 OBJ: F.3.1.1 47. ANS: friction DIF: L3 REF: p. F-88 OBJ: F.3.2.3 STO: 5.6.B.1, 5.6.A.2 48. ANS: hot spot DIF: L1 REF: p. F-85 OBJ: F.3.1.2, 5.1.B.3, 5.1.A.2 49. ANS: aa DIF: L2 REF: p. F-90 OBJ: F.3.2.3 STO: 5.6.A.2, 5.1.B.3 50. ANS: geyser DIF: L2 REF: p. F-105 OBJ: F.3.4.3 STO: 5.7.B.3 51. ANS: converging DIF: L2 REF: p. F-84 OBJ: F.3.1.1 52. ANS: geothermal DIF: L1 REF: p. F-105 OBJ: F.3.4.3 STO: 5.7.B.3 53. ANS: island arc DIF: L2 REF: p. F-84 OBJ: F.3.1.1 54. ANS: viscosity DIF: L1 REF: p. F-88 OBJ: F.3.2.2 STO: 5.6.B.1, 5.6.A.2 55. ANS: lava DIF: L2 REF: p. F-82 OBJ: F.3.1.1, 5.1.B.1 56. ANS: silica DIF: L2 REF: p. F-89 OBJ: F.3.2.3 STO: 5.1.B.3, 5.6.A.2

57. ANS: crater DIF: L1 REF: p. F-92 OBJ: F.3.3.1 58. ANS: dome mountain DIF: L2 REF: p. F-104 OBJ: F.3.4.2, 5.7.B.3 59. ANS: ash DIF: L1 REF: p. F-95 OBJ: F.3.3.2 60. ANS: pyroclastic flow DIF: L1 REF: p. F-95 OBJ: F.3.3.2 SHORT ANSWER 61. ANS: Diagram A shows a cinder cone volcano. It forms when cinders erupt again and again, piling up around the vent to form a steep, cone-shaped hill. DIF: L2 REF: p. F-100 OBJ: F.3.4.1 62. ANS: Diagram B shows a composite volcano. It forms when lava flows alternate with explosive eruptions of ash, cinder, and bombs. DIF: L2 REF: p. F-101 OBJ: F.3.4.1 63. ANS: Diagram C shows a shield volcano. It forms when repeated lava flows build up a broad, gently sloping mountain. DIF: L2 REF: p. F-100 OBJ: F.3.4.1 64. ANS: the Hawaiian Islands DIF: L2 REF: p. F-100 OBJ: F.3.4.1 65. ANS: A: explosive; B: both at different times; C: quiet DIF: L3 REF: p. F-100, p. F-101 OBJ: F.3.4.1 66. ANS: The top of the volcano will sink down, leaving a large hole, or caldera. A caldera forms as the roof of a volcano s empty magma chamber collapses. DIF: L3 REF: p. F-102 OBJ: F.3.4.1 67. ANS: As the oceanic plate is subducted, the plate melts and forms magma, which rises toward the surface and erupts as lava, forming volcanoes. DIF: L3 REF: p. F-83 OBJ: F.3.1.1

68. ANS: in the Pacific Northwest, including Oregon, Washington, and northern California DIF: L2 REF: p. F-84 OBJ: F.3.1.1 69. ANS: Volcanoes also can form at hot spots in the middle of continental or oceanic plates. At a hot spot, magma melts through the crust and moves to the surface. Another exception is a collision between two oceanic plates. In such a collision, one of the oceanic plates is subducted. The result is the melting of the plate and the formation of magma, which erupts to form a chain of volcanic islands called an island arc. DIF: L3 REF: p. F-85 OBJ: F.3.1.2, 5.1.B.3, 5.1.A.2 70. ANS: The part of the diagram labeled A shows a diverging plate boundary. Two oceanic plates diverge to form a mid-ocean ridge. DIF: L3 REF: p. F-83 OBJ: F.3.1.1 71. ANS: Magma erupts as lava through cracks in the crust along the central valley of the mid-ocean ridge. DIF: L3 REF: p. F-83 OBJ: F.3.1.1 72. ANS: B shows a converging plate boundary, where an oceanic plate collides with a continental plate. As a result of this collision, the oceanic plate sinks beneath a deep-ocean trench into the mantle. DIF: L3 REF: p. F-84 OBJ: F.3.1.1 ESSAY 73. ANS: The trapped gases in magma are under tremendous pressure. As magma rises to the surface, the pressure decreases and the gases begin to separate out. When the magma finds an opening, the gases rush out and carry the magma with them. DIF: L3 REF: p. F-92, p. F-93 OBJ: F.3.3.1 74. ANS: An eruption could cause landslides or avalanches of mud, melted snow, or rock. If an explosive eruption occurs, clouds of hot, burning gases could injure people. Ash could bury the village, damage crops, and clog car engines. DIF: L3 REF: p. F-94, p. F-95, p. F-96 OBJ: F.3.3.2 STO: 5.1.B.3, 5.6.A.2, 5.8.C.1, 5.2.B.1 75. ANS: A dormant volcano may not erupt for thousands of years. However, the volcano s body of magma may heat nearby groundwater, creating hot springs or geysers. DIF: L3 REF: p. F-104, p. F-105 OBJ: F.3.4.3, 5.7.B.3 76. ANS:

The volcano is likely to have a quiet eruption. Lava that is low in silica is thin and runny, so it flows easily and oozes quietly from the vent. DIF: L3 REF: p. F-94 OBJ: F.3.3.2 STO: 5.1.B.3, 5.6.A.2 77. ANS: Both landforms develop as a result of the upward movement of molten material. Lava plateaus are high, level areas that form when thin, runny lava repeatedly erupts on the surface. In contrast, dome mountains are high, dome-shaped areas that form when hardened magma is uplifted and bends the layers of rock above it into a dome. DIF: L3 REF: p. F-101, p. F-104 OBJ: F.3.4.1, F.3.4.2, 5.7.B.3 78. ANS: The physical properties of a substance are the characteristics that can be observed or measured without changing the composition of the substance. Examples include density, hardness, melting point, boiling point, and whether a substance is magnetic. The chemical properties of a substance are any property that produces a change in the composition of matter. Examples include the ability to burn and to combine with other substances. DIF: L3 REF: p. F-88 OBJ: F.3.2.1 STO: 5.6.B.1, 5.6.A.2 79. ANS: An active volcano is one that is erupting or has shown signs that it may erupt in the near future. A dormant volcano may awaken in the future and become active. A long time may pass before this happens. An extinct volcano is unlikely to erupt again. DIF: L3 REF: p. F-97, p. F-98 OBJ: F.3.3.3, 5.2.B.1, 5.2.A.2 80. ANS: In some liquids, there is a greater degree of friction among the liquid s particles. These liquids have higher viscosity than liquids whose particles have a lesser degree of friction. DIF: L2 REF: p. F-88 OBJ: F.3.2.2 STO: 5.6.B.1, 5.6.A.2