Name: Class: Date: 10. Some substances, when exposed to visible light, absorb more energy as heat than other substances absorb.

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1 Name: Class: Date: ID: A PS Chapter 13 Review Modified True/False Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true. 1. In all cooling systems, energy is transferred as heat from one substance to another, leaving the first substance with less energy and with a lower temperature. 2. As the temperature of mercury inside the thermometer increases, its volume increases. 3. On the Fahrenheit scale water freezes at 32 F. 4. A degree on the Fahrenheit scale is a bigger unit than a degree on the Celsius scale. 5. Energy is transferred as heat between two objects of same temperatures. 6. Energy is transferred as heat from a substance at high temperature to a substance at low temperature. 7. Heating by convection can occur only through solids. 8. A hot object emits less radiation than a cool object emits. 9. Radiation is the only method of energy transfer that can take place in a vacuum. 10. Some substances, when exposed to visible light, absorb more energy as heat than other substances absorb. 11. A good insulator is a poor conductor. Specific Heats at 25 C Substance c (J/kg K) Substance c (J/kg K) Water (liquid) 4186 Copper 385 Steam 1870 Gold 129 Ammonia (gas) 2060 Iron 449 Ethanol (liquid) 2440 Mercury 140 Aluminum 897 Lead 129 Carbon (graphite) 709 Silver It takes more heat energy to raise the temperature of water by one degree than to raise the temperature of steam by the same amount. 13. Insulation minimizes undesirable energy transfers. 14. People feel most comfortable when the temperature of the air is 98.6 F. 15. The R-value is a standard rating used to measure the effectiveness of insulation. 16. An active solar heating system needs sunlight and electricity as sources of energy. 1

2 Name: ID: A 17. The heat exchanger of a heating system uses conduction and convection to transfer energy as heat. 18. Some of the energy generated as heat by a heating system is wasted. R-Values for Some Common Building Materials Substance R-value Drywall, 1.3cm (0.50 in.) 0.45 Wood shingles, (overlapping) 0.87 Flat glass, cm (0.125 in.) 0.89 Hardwood siding, 2.54 cm (1.00 in.) 0.91 Vertical air space, 8.9 cm (3.5 in.) 1.01 Insulating glass, 0.64 cm (0.25 in.) 1.54 Cellulose fiber, 2.54 cm (1.00 in.) 3.70 Brick 10.2 cm (4.00 in.) 4.00 Fiberglass batting, 8.9 cm (3.5 in.) Vertical air space is a better insulator than fiberglass batting cm of brick is a better insulator than 10 cm of fiberglass batting. 21. The temperature of a volume of gas increases if the pressure of the gas or volume of the gas increases. 22. When a refrigerant evaporates it adds energy as heat to its surroundings. 23. When a refrigerant condenses it gives up energy as heat to its surroundings. 24. An example of an external combustion engine is a steam engine. Multiple Choice Identify the choice that best completes the statement or answers the question. 25. Temperature is a. associated with the sensation of hot and cold. b. proportional to the average kinetic energy of molecules. c. measured with thermometers. d. All of the above 26. What is 37.0 degrees Celsius on the Fahrenheit scale? a F c F b F d F 27. What is 175 F on the Celsius scale? a C c C b C d C 2

3 Name: ID: A 28. What is 175 C on the Kelvin scale? a. 76 K c. 98 K b. 89 K d. 448 K 29. As the kinetic energy of the molecules in a substance increases, the a. temperature of the substance increases. b. temperature of the substance decreases. c. potential energy of the substance changes. d. temperature remains the same. 30. The transfer of energy caused by the collision of molecules is called a. convection. c. contact. b. conduction. d. radiation. 31. The transfer of energy by the movement of fluids or gases with different temperatures is called a. convection. c. contact. b. conduction. d. radiation. 32. Energy from the sun reaches Earth by a. conduction and radiation. c. conduction and convection. b. radiation only. d. conduction only. 33. Convection currents rise in air because a. hot air rises and cold air remains stagnant. b. cool air descends and hot air rises. c. the molecules in hot air move faster. d. hot air has less friction. 34. Which method of energy transfer does not involve movement of matter? a. convection c. radiation b. conduction d. none of the above 35. Which of the following substances is the best conductor of transferring energy as heat? a. carbon dioxide gas c. iron b. water d. rubber 36. Suppose a fixed number of joules of energy is added as heat to 1 kg of the substances listed below. For which substance will the rise in temperature be the least? a. liquid ethanol c. water b. iron d. carbon 37. How much heat energy will cause the temperature of 7 kg of iron to increase its temperature by 15 K? The specific heat of iron is 449 J/kg K. a J c J b J d J 38. According to the first law of thermodynamics, a. there is no such thing as a perpetual motion machine. b. the energy of a system is constant. c. the total energy used in any process is conserved. d. in any process there is a decrease in potential energy. 3

4 Name: ID: A 39. Which of the following statements is true? a. Energy as heat flows from a lower temperature to a higher temperature. b. Energy as heat flows from a higher temperature to a lower temperature. c. The amount of heat in a closed system is a constant. d. Energy as heat flowing into an object is determined by the amount of work done on the object. 40. In an air conditioner, a substance that easily evaporates and condenses is used to transfer energy from a room to the air outside. When the substance evaporates, a. it absorbs energy as heat from the surrounding air. b. it transfers energy as heat to the surrounding air. c. energy is transferred by conduction. d. energy is transferred by convection. 41. The Fahrenheit temperature scale is defined by which of the following temperatures? a. Water boils at 100 degrees and freezes at 32 degrees. b. Water boils at 212 degrees and freezes at 32 degrees. c. Water evaporates at 212 degrees and freezes at 0 degrees. d. Liquid water turns to a gas at 100 degrees and to a solid at 0 degrees. 42. A cold-blooded reptile basks on a warm rock in the sun. Its body is warmed by a. radiation. c. convection. b. conduction. d. Both (a) and (b) 43. The temperature of a substance increases by 3 K when 1635 J is added to a 2 kg quantity of the substance. What is the specific heat of the substance? a. 242 J/kg K c. 300 J/kg K b. 272 J/kg K d. 817 J/kg K Specific Heats at 25 C Substance c (J/kg K) Substance c (J/kg K) Water (liquid) 4186 Copper 385 Steam 1870 Gold 129 Ammonia (gas) 2060 Iron 449 Ethanol (liquid) 2440 Mercury 140 Aluminum 897 Lead 129 Carbon (graphite) 709 Silver Using the table, determine which substance can absorb the most energy in a temperature increase of 1 K. a. liquid water c. gold b. aluminum d. lead 45. Which substance has a specific heat approximately 10 times greater than the specific heat of silver? a. water c. carbon b. ethanol d. mercury 46. The temperature of 1.5 kg of ethanol is 37 C. What will the final temperature be if J of energy as heat is added to the ethanol? a. 22 C c. 59 C b. 51 C d. 67 C 4

5 Name: ID: A kg of a substance underwent a 3 K change in temperature when J of energy as heat was added to the substance. What is the substance? a. gold c. copper b. water d. aluminum 48. A combustion engine uses what kind of energy to do work? a. radiation c. solar b. heat d. electrical Completion Complete each statement. 49. The measure of the average kinetic energy of all the particles within an object is called. 50. A(n) is a device for measuring temperature. 51. The temperature at which an object s energy is minimal is called. 52. The energy transferred between the particles of two objects because of the temperature difference between the two objects is called. 53. The energy transfer between particles as they collide within a substance or between two objects in contact is called. 54. The transfer of energy by the movement of fluids with different temperatures is called. 55. The movement of a gas or liquid due to expansion and contraction caused by temperature differences within the fluid is called a. 56. Radio waves, infrared radiation, visible light, ultraviolet rays, and X rays are forms of. 57. The transfer of energy by electromagnetic waves is called. 58. A(n) is a material through which energy can be easily transferred as heat. 59. A(n) is a material that is a poor energy conductor. 60. The amount of heat energy transferred that will raise the temperature of 1 kg of a substance by 1 K is called. 61. A(n) is any set of mechanisms arranged to transfer energy to a substance to raise the temperature of the substance. 62. A(n) is any set of mechanisms arranged to transfer energy from an object to lower its temperature. 63. A substance used in cooling systems that transfers large amounts of energy as it changes state is called a(n). 64. An automobile engine requires strokes for each cycle of the piston. 5

6 Name: ID: A Essay 65. Why is the human body like a heating system? 66. How can work increase the temperature of a substance? 67. What is the difference between a thermometer based on a bimetallic strip and a mercury thermometer? 68. Why do substances expand when heat energy is added to them? 69. Why is the lowest possible temperature 273 C? 70. What is the connection between heat and temperature? 71. Why do rocks in the desert get so hot? 72. At night, a rock in the desert will cool off. How could radiation, convection, and conduction explain how the rock gets colder? 73. How do convection currents form? 74. What is radiation and where does it come from? 75. What substances make the best conductors, and what substances make the best insulators? 76. What is specific heat? 77. What is the first law of thermodynamics? 78. Why does heat energy always move from a higher temperature to a lower temperature? 6

7 ID: A PS Chapter 13 Review Answer Section MODIFIED TRUE/FALSE 1. ANS: T PTS: 1 DIF: 2 REF: 3 2. ANS: T PTS: 1 DIF: 2 REF: 1 3. ANS: F, +32 PTS: 1 DIF: 2 REF: 1 4. ANS: F, smaller PTS: 1 DIF: 2 REF: 1 OBJ: 2 5. ANS: F, different PTS: 1 DIF: 2 REF: 1 OBJ: 2 6. ANS: T PTS: 1 DIF: 2 REF: 1 7. ANS: F, fluids PTS: 1 DIF: 3 REF: 2 8. ANS: F, more PTS: 1 DIF: 2 REF: 2 9. ANS: T PTS: 1 DIF: 2 REF: ANS: T PTS: 1 DIF: 2 REF: ANS: T PTS: 1 DIF: 2 REF: 2 OBJ: ANS: T PTS: 1 DIF: 2 REF: ANS: T PTS: 1 DIF: 1 REF: ANS: F, PTS: 1 DIF: 1 REF: ANS: T PTS: 1 DIF: 1 REF: 3 OBJ: ANS: T PTS: 1 DIF: 2 REF: 3 OBJ: ANS: F, radiation PTS: 1 DIF: 2 REF: 3 OBJ: 2 1

8 ID: A 18. ANS: T PTS: 1 DIF: 1 REF: 3 OBJ: ANS: F, worse PTS: 1 DIF: 1 REF: 3 OBJ: ANS: F, worse PTS: 1 DIF: 2 REF: 3 OBJ: ANS: T PTS: 1 DIF: 2 REF: 3 OBJ: ANS: F, subtracts PTS: 1 DIF: 2 REF: 3 OBJ: ANS: T PTS: 1 DIF: 2 REF: 3 OBJ: ANS: T PTS: 1 DIF: 2 REF: 3 MULTIPLE CHOICE 25. ANS: D PTS: 1 DIF: 1 REF: ANS: A PTS: 1 DIF: 2 REF: 1 OBJ: ANS: B PTS: 1 DIF: 2 REF: 1 OBJ: ANS: C PTS: 1 DIF: 2 REF: 1 OBJ: ANS: A PTS: 1 DIF: 2 REF: ANS: B PTS: 1 DIF: 1 REF: ANS: A PTS: 1 DIF: 2 REF: ANS: B PTS: 1 DIF: 2 REF: ANS: B PTS: 1 DIF: 2 REF: ANS: C PTS: 1 DIF: 2 REF: ANS: C PTS: 1 DIF: 2 REF: 2 OBJ: ANS: C PTS: 1 DIF: 2 REF: ANS: A PTS: 1 DIF: 1 REF: 2 2

9 ID: A 38. ANS: C PTS: 1 DIF: 2 REF: ANS: B PTS: 1 DIF: 1 REF: ANS: A PTS: 1 DIF: 2 REF: ANS: D PTS: 1 DIF: 2 REF: ANS: D PTS: 1 DIF: 2 REF: ANS: B PTS: 1 DIF: 2 REF: ANS: A PTS: 1 DIF: 2 REF: ANS: B PTS: 1 DIF: 2 REF: ANS: C PTS: 1 DIF: 2 REF: ANS: C PTS: 1 DIF: 2 REF: ANS: B PTS: 1 DIF: 2 REF: 3 COMPLETION 49. ANS: temperature PTS: 1 DIF: 2 REF: ANS: thermometer PTS: 1 DIF: 1 REF: ANS: absolute zero PTS: 1 DIF: 1 REF: 1 OBJ: ANS: heat PTS: 1 DIF: 1 REF: ANS: conduction PTS: 1 DIF: 1 REF: ANS: convection PTS: 1 DIF: 1 REF: ANS: convection current PTS: 1 DIF: 1 REF: 2 3

10 ID: A 56. ANS: electromagnetic waves PTS: 1 DIF: 1 REF: ANS: radiation PTS: 1 DIF: 1 REF: ANS: conductor PTS: 1 DIF: 1 REF: 2 OBJ: ANS: insulator PTS: 1 DIF: 1 REF: 2 OBJ: ANS: specific heat PTS: 1 DIF: 2 REF: ANS: heating system PTS: 1 DIF: 1 REF: ANS: cooling system PTS: 1 DIF: 2 REF: ANS: refrigerant PTS: 1 DIF: 1 REF: 3 OBJ: ANS: four PTS: 1 DIF: 1 REF: 3 ESSAY 65. ANS: The body must maintain a constant body temperature of about 37 C (98.6 F). If a person is surrounded by cool air, heat energy will be transferred to the air and the temperature of the skin will drop. Energy is transferred to the skin by the circulation of warm blood. The blood gets energy from body cells that burn nutrients. PTS: 1 DIF: 2 REF: ANS: One way is by exerting a force against friction, as you do when you rub your hands together to keep them warm on a cold day. If the force does nothing but overcome friction, all of the work done is converted into heat energy. PTS: 1 DIF: 2 REF: 3 4

11 ID: A 67. ANS: Most substances expand when heated. In liquid thermometers, the liquid is placed in a long narrow tube, which makes the expansion visible and provides a method for measuring temperature. Metals expand at different rates when heated. In a bimetallic thermometer two different metal strips are welded together. Changes in temperature cause the metal strips to bend because one metal strip expands more than the other metal strip. PTS: 1 DIF: 2 REF: ANS: Substances and objects are made of particles that are bound together and yet vibrate back and forth. When heat energy is added, the movement of the particles increases. The greater the movement, the more the substance will expand. PTS: 1 DIF: 2 REF: ANS: At the lowest temperature, which also equals 0 K, the kinetic energy of the particles is minimal and cannot be made any lower. Therefore, the temperature cannot drop any lower. PTS: 1 DIF: 2 REF: 1 OBJ: ANS: Temperature is the measure of the average kinetic energy of all the particles within an object. Heat is the kinetic energy transferred from the particles of one object to those of another object because of a temperature difference between the two objects. PTS: 1 DIF: 2 REF: ANS: Rocks in a desert are exposed to sunlight for the entire day. Energy from the sun is absorbed as heat by the rocks through radiation. PTS: 1 DIF: 2 REF: ANS: At night, a rock will stop absorbing heat energy from the sun and start radiating its own heat energy to the surrounding air, which will have a lower temperature. The rock will lose energy by conduction. Furthermore, a night breeze may blow cool air over the rock, causing the rock to give up energy. This process is an example of convection. PTS: 1 DIF: 3 REF: ANS: When air becomes hot it expands and the air becomes less dense. This decrease in density causes the air to rise. As the air moves up, it cools down, becomes more dense, and sinks. Thus, there is a continuous cycle of rising and falling air. PTS: 1 DIF: 2 REF: 2 5

12 ID: A 74. ANS: Radiation refers to radio waves, infrared radiation, visible light, X rays, and other forms of electromagnetic waves. All objects emit infrared radiation. Radiation from the sun is produced by nuclear fusion. There are also many other sources of electromagnetic radiation. PTS: 1 DIF: 2 REF: ANS: Gas is a very poor conductor because its particles are far apart, which makes the necessary collisions rare. Liquids are naturally better conductors and solids better still. Metals are better conductors than nonmetals. Substances that are poor conductors are good insulators. PTS: 1 DIF: 2 REF: 2 OBJ: ANS: Specific heat is the amount of heat energy required to raise the temperature of 1 kg of a substance by 1 C (or 1 K). PTS: 1 DIF: 1 REF: ANS: The first law of thermodynamics is the same as the law of conservation of energy. It states that the total energy used in any process is constant. PTS: 1 DIF: 2 REF: ANS: Heat energy is transferred because particles with a higher average kinetic energy collide with particles with a lower average kinetic energy. This decreases the average kinetic energy of the particles in the high temperature region and increases the average kinetic energy of the particles in the low temperature region. The result is that heat energy is transferred from high temperatures to low temperatures. PTS: 1 DIF: 2 REF: 3 6