Chemistry 122 – Practice Exam Matching Match each item with the correct statement below. a. calorimeter d. b. calorie e. c. joule f. enthalpy specific heat heat capacity ____ 1. quantity of heat needed to change the temperature of 1 g of a substance by 1 C ____ 2. quantity of heat needed to change the temperature of an object by 1 C ____ 3. heat content of a system at constant pressure Match each item with the correct statement below. a. substituent e. b. structural isomers f. c. geometric isomers g. d. stereoisomers asymmetric carbon trans configuration cis configuration ____ 4. arrangement in which substituted groups are on the same side of a double bond ____ 5. arrangement in which substituted groups are on opposite sides of a double bond ____ 6. compounds that differ in the orientation of groups around a double bond ____ 7. carbon atom to which four different atoms or groups are attached Match each item with the correct statement below. a. condensed structural formula d. b. homologous series e. c. unsaturated compound saturated compound complete structural formula ____ 8. formula showing all the atoms and bonds in a molecule ____ 9. structural formula in which some bonds and/or atoms are left out ____ 10. organic compound that contains at least one double or triple carbon-carbon bond Match each item with the correct statement below. a. substitution reaction d. b. addition reaction e. c. hydration reaction hydrogenation reaction dehydrogenation reaction ____ 11. a reaction in which an atom or group of atoms replaces another atom or group of atoms ____ 12. a reaction involving the addition of hydrogen to a carbon—carbon double bond to produce an alkane ____ 13. a reaction involving the addition of water to an alkene ____ 14. a reaction involving the loss of hydrogen Multiple Choice Identify the choice that best completes the statement or answers the question. ____ 15. What happens to the energy produced by burning gasoline in a car engine? a. The energy is lost as heat in the exhaust. b. The energy is transformed into work to move the car. c. The energy heats the parts of the engine. d. all of the above ____ 16. A piece of metal is heated, then submerged in cool water. Which statement below describes what happens? a. The temperature of the metal will increase. b. The temperature of the water will increase. c. The temperature of the water will decrease. d. The temperature of the water will increase and the temperature of the metal will decrease. ____ 17. What would likely happen if you were to touch the flask in which an endothermic reaction were occurring? a. b. c. d. The flask would probably feel cooler than before the reaction started. The flask would probably feel warmer than before the reaction started. The flask would feel the same as before the reaction started. none of the above ____ 18. If heat is released by a chemical system, an equal amount of heat will be ____. a. absorbed by the surroundings c. released by the surroundings b. absorbed by the universe d. released by the universe ____ 19. Which of the following is transferred due to a temperature difference? a. chemical energy c. electrical energy b. mechanical energy d. heat ____ 20. In an exothermic reaction, the energy stored in the chemical bonds of the reactants is ____. a. equal to the energy stored in the bonds of the products b. greater than the energy stored in the bonds of the products c. less than the energy stored in the bonds of the products d. less than the heat released ____ 21. When your body breaks down sugar completely, how much heat is released compared to burning the same amount of sugar in a flame? a. The body releases more heat. b. The body releases less heat. c. The body releases the same amount of heat. d. The body releases no heat. ____ 22. A piece of candy has 5 Calories (or 5000 calories). If it could be burned, leaving nothing but carbon dioxide and water, how much heat would it give off? a. 500 calories c. 5000 joules b. 5 kilocalories d. Not enough information is given. ____ 23. How many joules are in 148 calories? (1 cal = 4.18 J) a. 6.61 J c. b. 35.4 J d. ____ 24. What is the amount of heat required to raise the temperature of 200.0 g of aluminum by 10 C? (specific heat of aluminum = 0.21 a. b. ____ ) 420 cal 4200 cal c. d. 42,000 cal 420,000 cal 25. What is the specific heat of a substance if 1560 cal are required to raise the temperature of a 312-g sample by 15 C? a. c. 0.033 0.99 b. ____ 148 J 619 J d. 0.33 1.33 26. How many kilocalories of heat are required to raise the temperature of 225 g of aluminum from 20 C to 100 C? (specific heat of aluminum = 0.21 a. b. 0.59 kcal 3.8 kcal ) c. d. 85 kcal none of the above ____ 27. The heat capacity of an object depends in part on its ____. a. mass c. shape b. enthalpy d. potential energy ____ 28. Which of the following is a valid unit for specific heat? a. c. b. ____ cal d. C 29. When 45 g of an alloy, at 25 C, are dropped into 100.0 g of water, the alloy absorbs 956 J of heat. If the final temperature of the alloy is 37 C, what is its specific heat? a. b. ____ c. 0.423 d. 1.77 30. The specific heat of silver is 0.24 9.88 48.8 . How many joules of energy are needed to warm 4.37 g of silver from 25.0 C to 27.5 C? a. 2.62 J b. 0.14 J c. d. 45.5 J 0.022 J ____ 31. Which of the following substances has the highest specific heat? a. steel c. alcohol b. water d. chloroform ____ 32. By what quantity must the heat capacity of an object be divided to obtain the specific heat of that material? a. its mass c. its temperature b. its volume d. its energy ____ 33. The amount of heat transferred from an object depends on which of the following? a. the specific heat of the object c. the mass of the object b. the initial temperature of the object d. all of the above ____ 34. On what principle does calorimetry depend? a. Hess's law b. law of conservation of energy c. d. law of enthalpy law of multiple proportions ____ 35. How can the enthalpy change be determined for a reaction in an aqueous solution? a. by knowing the specific heat of the reactants b. by mixing the reactants in a calorimeter and measuring the temperature change c. by knowing the mass of the reactants d. The enthalpy change for this type of reaction cannot be determined. ____ 36. Calculate the energy required to produce 7.00 mol Cl O 2Cl (g) + 7O (g) + 130 kcal a. 7.00 kcal b. 65 kcal ____ 2Cl O (g) c. d. 130 kcal 455 kcal 37. What is the standard heat of reaction for the following reaction? Zn(s) + Cu (aq) Zn (aq) + Cu(s) ( H for Cu = +64.4 kJ/mol; a. 216.8 kJ released per mole b. 88.0 kJ released per mole ____ on the basis of the following balanced equation. H for Zn = –152.4 kJ/mol) c. 88.0 kJ absorbed per mole d. 216.8 kJ absorbed per mole 38. Calculate H for the following reaction. C H (g) + H (g) C H (g) ( H for C H (g) = 52.5 kJ/mol; a. –137.2 kJ b. –32.2 kJ H for C H (g) = –84.7 kJ/mol) c. 32.2 kJ d. 137.2 kJ ____ 39. What is the heat of solution? a. the amount of heat required to change a solid into a liquid b. the amount of heat absorbed or released when a solid dissolves c. the amount of heat required to change a vapor into a liquid d. the amount of heat released when a vapor changes into a liquid ____ 40. The H is ____. a. always negative b. always positive c. sometimes positive, sometimes negative d. always 0 = –445.1 kJ/mol) dissolves in 10 L of water, how much heat is released? c. 11.1 J d. 11.1 kJ ____ 41. When 1.0 g of solid NaOH ( H a. 445.1 kJ b. 405.1 kJ ____ 42. When 10 g of diethyl ether is converted to vapor at its boiling point, about how much heat is absorbed? (C H O, = 15.7 kJ/mol, boiling point: 34.6 C) a. b. ____ ____ ____ 2 kJ 2J c. d. 43. Hess's law ____. a. makes it possible to calculate H for complicated chemical reactions b. states that when you reverse a chemical equation, you must change the sign of c. determines the way a calorimeter works d. describes the vaporization of solids H 44. Using a table that lists standard heats of formation, you can calculate the change in enthalpy for a given chemical reaction. The change in enthalpy is equal to ____. a. H of products minus H of reactants b. H of products plus c. H of reactants minus d. H of products divided by H of reactants H of products H of reactants 45. Calculate H for the reaction of sulfur dioxide with oxygen. 2SO (g) + O (g) 2SO (g) ( H SO (g) = –296.8 kJ/mol; a. –98.9 kJ b. –197.8 kJ ____ 0.2 kJ Not enough information is given. H SO (g) = –395.7 kJ/mol) c. 197.8 kJ d. Not enough information is given. 46. Which expression represents a reaction rate? a. time/mass b. number/time c. d. energy/time time/energy ____ 47. Activation energy is ____. a. the heat released in a reaction b. an energy barrier between reactants and products c. the energy given off when reactants collide d. generally very high for a reaction that takes place rapidly ____ 48. Why does a higher temperature cause a reaction to go faster? a. There are more collisions per second only. b. Collisions occur with greater energy only. c. There are more collisions per second and the collisions are of greater energy. d. There are more collisions per second or the collisions are of greater energy. ____ 49. Why does a catalyst cause a reaction to proceed faster? a. There are more collisions per second only. b. The collisions occur with greater energy only. c. The activation energy is lowered only. d. There are more collisions per second and the collisions are of greater energy. ____ 50. What happens to a catalyst in a reaction? a. It is unchanged. b. It is incorporated into the products. c. d. It is incorporated into the reactants. It evaporates away. ____ 51. The rate of a chemical reaction normally ____. a. decreases as temperature increases b. is slowed down by a catalyst c. increases as reactant concentration increases d. decreases as reactant concentration increases ____ 52. Which of the following substances act as catalysts in the body? a. carbohydrates c. lipids H b. nucleic acids d. enzymes ____ 53. At equilibrium, what is the rate of production of reactants compared with the rate of production of products? a. much higher c. the same b. higher d. lower ____ 54. If a reaction is reversible, what are the relative amounts of reactant and product at the end of the reaction? a. no reactant; all product b. no product; all reactant c. some product; some reactant d. The relationship between reactants and products cannot be determined. ____ 55. If sulfur dioxide and oxygen can be made into sulfur trioxide, what is the reverse reaction? a. 2SO 2SO + O c. 2SO + O 2SO b. SO + O SO d. SO + 2SO 3S + 4O ____ 56. What happens to a reaction at equilibrium when more reactant is added to the system? a. The reaction makes more products. c. The reaction is unchanged. b. The reaction makes more reactants. d. The answer cannot be determined. ____ 57. In an endothermic reaction at equilibrium, what is the effect of raising the temperature? a. The reaction makes more products. c. The reaction is unchanged. b. The reaction makes more reactants. d. The answer cannot be determined. ____ 58. What is the equilibrium constant for the following reaction? C+O CO a. c. b. ____ d. 59. In an equilibrium reaction with a K a. b. reactants are favored reaction is spontaneous of 1 10 , the ____. c. d. the products are favored reaction is exothermic ____ 60. The amount of disorder in a system is measured by its ____. a. activation energy c. equilibrium position b. entropy d. K ____ 61. If a system is left to change spontaneously, in what state will it end? a. the same state in which it began b. the state with lowest possible energy c. the state with the maximum disorder d. the state with the lowest possible energy consistent with the state of maximum disorder ____ 62. Which reaction results in the greatest increase in entropy? a. A B c. 2A B b. A 2B d. 3A B ____ 63. Which of the following statements explains why the melting of ice is a spontaneous reaction at room temperature and pressure? a. Melting is accompanied by a decrease of entropy. b. Melting is accompanied by an increase of entropy. c. Melting is accompanied by a decrease of energy. d. Melting is accompanied by an increase of energy. ____ 64. The melting of ice at temperatures above 0 C ____. a. liberates heat c. b. is not spontaneous d. ____ is not favorable is endothermic 65. When an acid reacts with a base, what compounds are formed? a. a salt only c. metal oxides only b. water only d. a salt and water ____ 66. What is a property of a base? a. bitter taste b. watery feel c. d. strong color unreactive ____ 67. What is an acid according to Arrhenius? a. a substance that ionizes to yield protons in aqueous solution b. a substance that is a hydrogen ion donor c. a substance that accepts an electron pair d. a substance that is a hydrogen ion acceptor ____ 68. Which of these is an Arrhenius base? a. LiOH b. ____ NH 69. What type of acid is sulfuric acid? a. monoprotic b. diprotic c. H PO d. CH COOH c. d. triprotic none of the above ____ 70. Which compound can act as both a Brønsted-Lowry acid and a Brønsted-Lowry base? a. water c. sodium hydroxide b. ammonia d. hydrochloric acid ____ 71. Which of the following reactions illustrates amphoterism? a. H O + H O c. HCl + H O H O + OH b. NaCl d. NaOH Na + OH Na ____ 72. What are the acids in the following equilibrium reaction? CN + H O HCN + OH a. CN , H O c. CN , OH b. H O, HCN d. H O, OH ____ 73. What is the charge on the hydronium ion? a. 2– b. 2– c. d. H O + Cl + OH 0 1+ ____ 74. If the hydrogen ion concentration of a solution is 10 M, is the solution acidic, alkaline, or neutral? a. acidic c. neutral b. alkaline d. The answer cannot be determined. ____ 75. What is pH? a. the negative logarithm of the hydrogen ion concentration b. the positive logarithm of the hydrogen ion concentration c. the negative logarithm of the hydroxide ion concentration d. the positive logarithm of the hydroxide ion concentration ____ 76. What characterizes a strong acid or base? a. polar covalent bonding b. complete ionization in water c. ionic bonding d. presence of a hydroxide or hydrogen ion ____ 77. What is another name for the acid dissociation constant? a. equilibrium constant c. rate constant b. ionization constant d. mole fraction ____ 78. A 0.12M solution of an acid that ionizes only slightly in solution would be termed ____. a. concentrated and weak c. dilute and weak b. strong and dilute d. concentrated and strong ____ 79. A substance with a K of 1 a. strong acid b. weak acid 10 would be classified as a ____. c. strong base d. weak base ____ 80. The ionization constant (K ) of HF is 6.7 a. [HF] is greater than [H ][F ]. b. . Which of the following is true in a 0.1M solution of this acid? c. [HF] is equal to [H ][F ]. d. [HF] is less than [H ][F ]. 10 10 [HF] is equal to [H ][F ]. ____ 81. If an acid has a K = 1.6 a. acidic b. basic , what is the acidity of the solution? c. neutral d. The answer cannot be determined. ____ 82. In a titration, when the number of moles of hydrogen ions equals the number of moles of hydroxide ions, what is said to have happened? a. The equivalence point has been reached. b. The end point has been reached. c. The point of neutralization has been reached. d. The titration has failed. ____ 83. How many covalent bonds can each carbon atom form? a. 1 c. 3 b. 2 d. 4 ____ 84. The name for an alkyl group that contains two carbon atoms is ____. a. diphenyl c. dimethyl b. ethyl d. ethane ____ 85. What is the general formula for a straight-chain alkane? a. C H c. C H b. C H d. C H ____ 86. What is the condensed structural formula for 2,2-dimethylbutane? a. CH (CH ) CH c. (CH ) CCH CH b. CH CH CH CH CH d. C H (CH ) ____ 87. What is the name of the compound CH CH(CH )C(CH ) ? a. 2,2,3-trimethylbutane c. 1,1,1,2-tetramethylpropane b. tetramethylpropane d. isoheptane ____ 88. Why are the molecules of hydrocarbons nonpolar? a. The intermolecular attractions are strong. b. All the bonds are single covalent bonds. c. The electron pair is shared almost equally in all the bonds. d. Van der Waals forces overcome polarity. ____ 89. Which of the following compounds is an unsaturated hydrocarbon? a. methane c. nonane b. propyne d. methyl ____ 90. Which of these compounds is an alkene? a. methane b. nonene c. d. butyne propanone ____ 91. Which of the following compounds is a structural isomer of butane? a. 2-methylbutane c. 2-methylpropane b. 2,2-dimethylbutane d. 2,2-diethylpropane ____ 92. Which of the following is true about structural isomers? a. Structural isomers have the same molecular formula. b. Structural isomers have different physical and chemical properties. c. Structural isomers have the same elemental composition. d. all of the above ____ 93. A structural isomer of hexane is ____. a. 2,2-dimethylbutane b. cyclohexane c. d. benzene 2-methylpentene ____ ____ ____ 94. Alkanes do not have geometric isomers because the carbon atoms in their carbon-carbon bonds are ____. a. double bonds c. free to rotate b. quite polar d. asymmetric 95. How many different atoms or groups are attached to an asymmetric carbon? a. 2 c. 6 b. 4 d. 8 96. What is the name of the functional group in the following compound? a. b. ____ c. d. isopropyl bromide tert-butyl bromide c. d. isobutyl bromide sec-butyl bromide 98. What is the carbon skeleton of the product formed in the following reaction? C H + HBr a. c. b. d. CCCBr ____ carbonyl carboxylic acid 97. What is the common name of the following compound? a. b. ____ halogen ester CCBrC 99. In an addition reaction, which bond of the reactant is broken? a. carbon—carbon single bond c. carbon—carbon double bond b. carbon—hydrogen single bond d. carbon—hydrogen double bond ____ 100. What type of compound is CH OCH CH CH ? a. alcohol c. ether b. aldehyde d. ketone ____ 101. Name the following compound. CH CH CH CH OC H a. cyclohexylbutyl ether b. butylcyclohexyl ether c. d. phenylbutyl ether butylphenyl ether c. d. 4-butanone 4-pentanone ____ 102. What is the name of the following compound? a. b. 2-butanone 2-pentanone ____ 103. Which carbon skeleton represents a ketone? a. b. c. d. ____ 104. A ketone has the general structure ____________. a. ROR b. c. d. ____ 105. What is the name of the following compound? a. b. butane butanal c. d. butanol butanone ____ 106. Which carbon skeleton contains a carboxyl group? a. c. CCCO b. d. ____ 107. Which carbon skeleton represents an ester? a. CCCCCOCC b. c. d. ____ 108. When an oxygen atom is attached to a carbon atom, the carbon atom becomes more ____. a. oxidized c. acidic b. reduced d. basic Short Answer 109. How many joules are there in 215 calories? (1 cal = 4.184 J) 110. How much heat is required to raise the temperature of 5.5 0.21 10 g of aluminum by 10 C? (specific heat of aluminum = ) 111. If 500 g of iron absorbs 22,000 cal of heat, what will be the change in temperature? (specific heat of iron = 0.11 ) 112. A 55.0-g piece of copper wire is heated, and the temperature of the wire changes from 19.0 C to 86.0 C. The amount of heat absorbed is 343 cal. What is the specific heat of copper? 113. The specific heat capacity of graphite is 0.71 . Calculate the energy required to raise the temperature of 750 g of graphite by 160 C. 114. It takes 770 joules of energy to raise the temperature of 50.0 g of mercury by 110 C. What is the specific heat of mercury? 115. When 64.0 g of methanol (CH OH) is burned, 1454 kJ of energy is produced. What is the heat of combustion for methanol? 116. How much heat is required to melt 1.6 moles of NaCl ( H = 30.2 kJ/mol) at its melting point? 117. Suppose a substance has a heat of fusion equal to 45 cal/g and a specific heat of 0.75 in the liquid state. If 5.0 kcal of heat are applied to a 50-g sample of the substance at a temperature of 24 C, what will its new temperature be? What state will the sample be in? (melting point of the substance = 27 C; specific heat of the solid = 0.48 ; boiling point of the substance = 700 C) 118. Consider a 67-g chunk of ice ( H = 6.0 kJ/mol) in a beaker immersed in a water bath. To produce just enough heat to melt the ice, how many moles of solid NaOH ( H = –445.1 kJ/mol) must you dissolve in the water bath? 119. If you supply 36 kJ of heat, how many moles of ice at 0 C can be melted, heated to its boiling point, and completely boiled away? ( H = 40.5 kJ/mol; H 120. Use the information below to calculate 2NO (g) N O (g) 2N (g) + 2O (g) 2NO (g) H H = 6.0 kJ/mol; specific heatwater = 0.0753 ) for the following reaction. = 67.7 kJ N (g) + 2O (g) N O (g) H = 9.7 kJ 121. What is the equilibrium constant for the following reaction? Si + O SiO 122. What is the ion-product constant for water? 123. If the [H ] in a solution is 1 10 mol/L, what is the [OH ]? 124. Calculate the hydrogen-ion concentration [H ] for an aqueous solution in which [OH ] is 1 solution acidic, basic, or neutral? 125. A liter of impure water has 10 water? 10 mol/L. Is this mol of hydroxide ions. What is the concentration of hydronium ions in this sample of 126. If the hydroxide-ion concentration is 1 10 M, what is the pH of the solution? 127. If the hydrogen-ion concentration is 1 10 M, what is the pOH of the solution? 128. What is the hydrogen-ion concentration if the pH is 3.7? 129. A 0.500M solution of a weak acid, HX, is only partially ionized. The [H ] was found to be 4.02 10 M. Find the dissociation constant for this acid. 130. What is the acid dissociation constant of a weak acid if a concentration of 0.3M gives a hydrogen-ion concentration of 0.001M? 131. Calculate the acid dissociation constant of a weak monoprotic acid if a 0.5M solution of this acid gives a hydrogen-ion concentration of 0.000 1M? 132. Write the general structure for aldehyde compounds. 133. What is the expected product when the following compound is oxidized? CH CH CH CH OH Numeric Response 134. If the hydrogen ion concentration is 10 135. If the hydroxide ion concentration is 10 136. If [OH ] = 1 10 M, what is the pH of the solution? M, what is the pH of the solution? M, what is the pH of the solution? 137. What is the pH of a solution with a concentration of 0.01M hydrochloric acid? 138. What is the pH when the hydrogen ion concentration is 7.0 10 M? 139. What percent of the composition of natural gas is methane? Essay 140. Explain the distinction between heat capacity and specific heat. Provide an example to illustrate this distinction. 141. Describe the parts of a calorimeter and the function of each part. 142. What is entropy? Give several examples. 143. Compare and contrast the properties of acids and bases. 144. What are acids and bases according to the Brønsted-Lowry theory? 145. What are acids and bases according to the Lewis theory? Give examples. 146. How is strength different from concentration for acids and bases? Give an example. 147. Explain why carbon is able to form such a large number of compounds. 148. Describe in your own words what the difference is between unsaturated and saturated hydrocarbons. What is a saturated compound saturated with? 149. Explain how geometric isomers differ from each other. Describe the difference between the trans and cis configurations of geometric isomers. Provide an example of each configuration for a molecule that has geometric isomers. 150. Why is burning coal a major source of pollution? 151. Describe what happens in a substitution reaction. Give an example of a substitution reaction and name the atoms involved in the replacement. d Answer Section MATCHING 1. ANS: OBJ: 2. ANS: OBJ: 3. ANS: OBJ: E PTS: 1 DIF: L1 REF: 17.1.3 Identify the units used to measure heat transfer. F PTS: 1 DIF: L1 REF: 17.1.3 Identify the units used to measure heat transfer. D PTS: 1 DIF: L1 REF: 17.2.1 Describe how calorimeters are used to measure heat flow. 4. ANS: OBJ: 5. ANS: OBJ: 6. ANS: OBJ: 7. ANS: OBJ: G 22.3.2 F 22.3.2 C 22.3.2 E 22.3.3 p. 508 p. 508 p. 511 PTS: 1 DIF: L1 REF: p. 705 Describe the conditions under which geometric isomerism is possible. PTS: 1 DIF: L1 REF: p. 705 Describe the conditions under which geometric isomerism is possible. PTS: 1 DIF: L1 REF: p. 705 Describe the conditions under which geometric isomerism is possible. PTS: 1 DIF: L1 REF: p. 705 Identify optical isomers. 8. ANS: OBJ: 9. ANS: OBJ: 10. ANS: OBJ: E PTS: 1 DIF: L1 REF: p. 696 22.1.2 Define and describe alkanes. A PTS: 1 DIF: L1 REF: p. 696 22.1.2 Define and describe alkanes. C PTS: 1 DIF: L1 REF: p. 702 22.2.1 Describe the difference between unsaturated and saturated hydrocarbons. 11. ANS: OBJ: 12. ANS: OBJ: 13. ANS: OBJ: 14. ANS: OBJ: A 23.1.3 D 23.2.3 C 23.2.3 E 23.3.4 PTS: 1 DIF: L1 REF: p. 728 Describe how halocarbons can be prepared. PTS: 1 DIF: L1 REF: p. 734 Name the reactions of alkenes that may be used to introduce functional groups. PTS: 1 DIF: L1 REF: p. 734 Name the reactions of alkenes that may be used to introduce functional groups. PTS: 1 DIF: L1 REF: p. 743 Explain how dehydration is an oxidation reaction. MULTIPLE CHOICE 15. ANS: OBJ: 16. ANS: OBJ: 17. ANS: OBJ: 18. ANS: OBJ: 19. ANS: OBJ: 20. ANS: OBJ: 21. ANS: D 17.1.1 D 17.1.1 A 17.1.1 A 17.1.1 D 17.1.1 B 17.1.1 C PTS: 1 DIF: L1 Explain how energy, heat, and work are related. PTS: 1 DIF: L1 Explain how energy, heat, and work are related. PTS: 1 DIF: L1 Explain how energy, heat, and work are related. PTS: 1 DIF: L1 Explain how energy, heat, and work are related. PTS: 1 DIF: L1 Explain how energy, heat, and work are related. PTS: 1 DIF: L2 Explain how energy, heat, and work are related. PTS: 1 DIF: L1 REF: p. 505 REF: p. 506 REF: p. 506 REF: p. 506 REF: p. 506 REF: p. 506 REF: p. 507 OBJ: 17.1.2 Classify processes as either exothermic or endothermic. 22. ANS: B PTS: 1 DIF: L2 REF: p. 507 OBJ: 17.1.2 Classify processes as either exothermic or endothermic. 23. ANS: D PTS: 1 DIF: L1 REF: p. 507 OBJ: 17.1.3 Identify the units used to measure heat transfer. 24. ANS: A PTS: 1 DIF: L1 REF: p. 508 OBJ: 17.1.3 Identify the units used to measure heat transfer. 25. ANS: B PTS: 1 DIF: L1 REF: p. 509 | p. 510 OBJ: 17.1.3 Identify the units used to measure heat transfer. 26. ANS: B PTS: 1 DIF: L1 REF: p. 508 OBJ: 17.1.3 Identify the units used to measure heat transfer. 27. ANS: A PTS: 1 DIF: L1 REF: p. 508 OBJ: 17.1.3 Identify the units used to measure heat transfer. 28. ANS: A PTS: 1 DIF: L1 REF: p. 508 OBJ: 17.1.3 Identify the units used to measure heat transfer. 29. ANS: B PTS: 1 DIF: L2 REF: p. 509 OBJ: 17.1.3 Identify the units used to measure heat transfer. 30. ANS: A PTS: 1 DIF: L2 REF: p. 509 | p. 510 OBJ: 17.1.3 Identify the units used to measure heat transfer. 31. ANS: B PTS: 1 DIF: L2 REF: p. 509 | p. 510 OBJ: 17.1.3 Identify the units used to measure heat transfer. 32. ANS: A PTS: 1 DIF: L2 REF: p. 509 | p. 510 OBJ: 17.1.3 Identify the units used to measure heat transfer. | 17.1.4 Distinguish between heat capacity and specific heat. 33. ANS: D PTS: 1 DIF: L1 REF: p. 512 OBJ: 17.2.1 Describe how calorimeters are used to measure heat flow. 34. ANS: B PTS: 1 DIF: L2 REF: p. 511 OBJ: 17.2.1 Describe how calorimeters are used to measure heat flow. 35. ANS: B PTS: 1 DIF: L2 REF: p. 512 OBJ: 17.2.1 Describe how calorimeters are used to measure heat flow. 36. ANS: D PTS: 1 DIF: L2 REF: p. 515 OBJ: 17.2.2 Construct thermochemical equations. | 17.2.3 Solve for enthalpy changes in chemical reactions by using heats of reaction. 37. ANS: A PTS: 1 DIF: L2 REF: p. 516 OBJ: 17.2.2 Construct thermochemical equations. 38. ANS: A PTS: 1 DIF: L2 REF: p. 516 OBJ: 17.2.2 Construct thermochemical equations. | 17.2.3 Solve for enthalpy changes in chemical reactions by using heats of reaction. 39. ANS: B PTS: 1 DIF: L1 REF: p. 525 OBJ: 17.3.2 Solve for the enthalpy change that occurs when a substance melts, freezes, boils, condenses, or dissolves. 40. ANS: C PTS: 1 DIF: L1 REF: p. 525 OBJ: 17.3.2 Solve for the enthalpy change that occurs when a substance melts, freezes, boils, condenses, or dissolves. 41. ANS: D PTS: 1 DIF: L2 REF: p. 526 OBJ: 17.3.2 Solve for the enthalpy change that occurs when a substance melts, freezes, boils, condenses, or dissolves. 42. ANS: A PTS: 1 DIF: L2 REF: p. 524 OBJ: 17.3.2 Solve for the enthalpy change that occurs when a substance melts, freezes, boils, condenses, or dissolves. 43. ANS: A PTS: 1 DIF: L1 REF: p. 527 OBJ: 17.4.1 State Hess's law of heat summation and describe how it is used in chemistry. 44. ANS: A PTS: 1 DIF: L1 REF: p. 530 OBJ: 17.4.2 Solve for enthalpy changes by using Hess' law or standard heats of formation. | 17.2.3 Solve for enthalpy changes in chemical reactions by using heats of reaction. 45. ANS: B PTS: 1 DIF: L2 REF: p. 531 OBJ: 17.4.2 Solve for enthalpy changes by using Hess' law or standard heats of formation. 46. ANS: OBJ: 47. ANS: OBJ: 48. ANS: OBJ: 49. ANS: OBJ: 50. ANS: OBJ: 51. ANS: OBJ: 52. ANS: OBJ: 53. ANS: OBJ: 54. ANS: OBJ: 55. ANS: OBJ: 56. ANS: OBJ: 57. ANS: OBJ: 58. ANS: OBJ: 59. ANS: OBJ: 60. ANS: OBJ: 61. ANS: OBJ: 62. ANS: OBJ: 63. ANS: OBJ: 64. ANS: OBJ: 65. ANS: OBJ: 66. ANS: OBJ: 67. ANS: OBJ: Lewis. 68. ANS: OBJ: Lewis. 69. ANS: OBJ: Lewis. 70. ANS: OBJ: B 18.1.1 B 18.1.1 C 18.1.2 C 18.1.2 A 18.1.2 C 18.1.2 D 18.1.2 C 18.2.1 C 18.2.1 A 18.2.1 A 18.2.2 A 18.2.2 B 18.2.3 C 18.2.3 B 18.4.2 D 18.4.2 B 18.4.2 B 18.4.2 D 18.4.3 D 19.4.1 A 19.1.1 A 19.1.2 PTS: 1 DIF: L1 REF: p. 542 Describe how to express the rate of a chemical reaction. PTS: 1 DIF: L1 REF: p. 543 Describe how to express the rate of a chemical reaction. PTS: 1 DIF: L1 REF: p. 545 Identify four factors that influence the rate of a chemical reaction. PTS: 1 DIF: L1 REF: p. 546 | p. 547 Identify four factors that influence the rate of a chemical reaction. PTS: 1 DIF: L1 REF: p. 546 Identify four factors that influence the rate of a chemical reaction. PTS: 1 DIF: L1 REF: p. 545 Identify four factors that influence the rate of a chemical reaction. PTS: 1 DIF: L2 REF: p. 547 Identify four factors that influence the rate of a chemical reaction. PTS: 1 DIF: L1 REF: p. 550 Describe how the amounts of reactants and products change in a chemical system at equilibrium. PTS: 1 DIF: L1 REF: p. 549 | p. 550 Describe how the amounts of reactants and products change in a chemical system at equilibrium. PTS: 1 DIF: L2 REF: p. 549 Describe how the amounts of reactants and products change in a chemical system at equilibrium. PTS: 1 DIF: L2 REF: p. 552 | p. 553 Identify three stresses that can change the equilibrium position of a chemical system. PTS: 1 DIF: L2 REF: p. 554 Identify three stresses that can change the equilibrium position of a chemical system. PTS: 1 DIF: L1 REF: p. 556 Explain what the value of Keq indicates about the position of equilibrium. PTS: 1 DIF: L1 REF: p. 556 Explain what the value of Keq indicates about the position of equilibrium. PTS: 1 DIF: L1 REF: p. 569 Describe the role of entropy in chemical reactions. PTS: 1 DIF: L2 REF: p. 569 Describe the role of entropy in chemical reactions. PTS: 1 DIF: L2 REF: p. 570 Describe the role of entropy in chemical reactions. PTS: 1 DIF: L2 REF: p. 569 Describe the role of entropy in chemical reactions. PTS: 1 DIF: L2 REF: p. 571 Identify two factors that determine the spontaneity of a reaction. PTS: 1 DIF: L1 REF: p. 587 Define the products of an acid-base reaction. PTS: 1 DIF: L1 REF: p. 588 Define the properties of acids and bases. PTS: 1 DIF: L1 REF: p. 588 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and A PTS: 1 DIF: L1 REF: p. 589 19.1.2 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and B PTS: 1 DIF: L2 REF: p. 588 19.1.2 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and A PTS: 1 DIF: L2 REF: p. 591 19.1.2 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and Lewis. 71. ANS: OBJ: Lewis. 72. ANS: OBJ: Lewis. 73. ANS: OBJ: 74. ANS: OBJ: 75. ANS: OBJ: 76. ANS: OBJ: 77. ANS: OBJ: 78. ANS: OBJ: 79. ANS: OBJ: 80. ANS: OBJ: 81. ANS: OBJ: 82. ANS: OBJ: 83. ANS: OBJ: 84. ANS: OBJ: 85. ANS: OBJ: 86. ANS: OBJ: 87. ANS: OBJ: 88. ANS: OBJ: 89. ANS: OBJ: 90. ANS: OBJ: 91. ANS: OBJ: 92. ANS: OBJ: 93. ANS: OBJ: 94. ANS: OBJ: 95. ANS: OBJ: A PTS: 1 DIF: L2 REF: p. 592 19.1.2 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and B PTS: 1 DIF: L2 REF: p. 591 19.1.2 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and D 19.2.1 B 19.2.1 A 19.2.2 B 19.3.1 B 19.3.1 C 19.3.2 B 19.3.3 A 19.3.3 D 19.3.3 A 19.4.4 D 22.1.1 B 22.1.2 D 22.1.2 C 22.1.2 A 22.1.2 C 22.1.3 B 22.2.1 B 22.2.2 C 22.3.1 D 22.3.1 A 22.3.1 C 22.3.2 B 22.3.3 PTS: 1 DIF: L1 REF: p. 594 Describe how [H+] and [OH+] are related in an aqueous solution. PTS: 1 DIF: L1 REF: p. 595 Describe how [H+] and [OH+] are related in an aqueous solution. PTS: 1 DIF: L1 REF: p. 596 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. PTS: 1 DIF: L1 REF: p. 605 Define strong acids and weak acids. PTS: 1 DIF: L2 REF: p. 607 Define strong acids and weak acids. PTS: 1 DIF: L3 REF: p. 609 Describe how an acid's strength is related to the value of its acid dissociation constant. PTS: 1 DIF: L2 REF: p. 607 Calculate an acid dissociation constant (Ka) from concentration and pH measurements. PTS: 1 DIF: L2 REF: p. 607 Calculate an acid dissociation constant (Ka) from concentration and pH measurements. PTS: 1 DIF: L2 REF: p. 610 Calculate an acid dissociation constant (Ka) from concentration and pH measurements. PTS: 1 DIF: L1 REF: p. 613 | p. 614 | p. 615 Describe the relationship between equivalence point and the end point of a titration. PTS: 1 DIF: L1 REF: p. 694 Describe the relationship between the valence electrons and bonding in carbon. PTS: 1 DIF: L1 REF: p. 698 Define and describe alkanes. PTS: 1 DIF: L2 REF: p. 695 Define and describe alkanes. PTS: 1 DIF: L2 REF: p. 696 | p. 698 Define and describe alkanes. PTS: 1 DIF: L2 REF: p. 698 Define and describe alkanes. PTS: 1 DIF: L2 REF: p. 700 Relate the polarity of hydrocarbons to their solubility. PTS: 1 DIF: L1 REF: p. 703 Describe the difference between unsaturated and saturated hydrocarbons. PTS: 1 DIF: L1 REF: p. 702 Distinguish between the structures of alkenes and alkynes. PTS: 1 DIF: L1 REF: p. 704 Explain why structural isomers have different properties. PTS: 1 DIF: L1 REF: p. 704 Explain why structural isomers have different properties. PTS: 1 DIF: L1 REF: p. 704 Explain why structural isomers have different properties. PTS: 1 DIF: L2 REF: p. 705 Describe the conditions under which geometric isomerism is possible. PTS: 1 DIF: L2 REF: p. 705 Identify optical isomers. 96. ANS: OBJ: 97. ANS: OBJ: 98. ANS: OBJ: 99. ANS: OBJ: 100. ANS: OBJ: 101. ANS: OBJ: 102. ANS: OBJ: 103. ANS: OBJ: 104. ANS: OBJ: 105. ANS: OBJ: 106. ANS: OBJ: 107. ANS: OBJ: 108. ANS: OBJ: B 23.1.1 B 23.1.2 B 23.1.3 C 23.2.3 C 23.2.4 D 23.2.4 B 23.3.1 B 23.3.1 B 23.3.1 D 23.3.1 C 23.3.2 C 23.3.3 A 23.3.4 PTS: 1 DIF: L1 REF: p. 726 Explain how organic compounds are classified. PTS: 1 DIF: L1 REF: p. 727 Identify halocarbons and the IUPAC rules for naming halocarbons. PTS: 1 DIF: L2 REF: p. 727 Describe how halocarbons can be prepared. PTS: 1 DIF: L1 REF: p. 733 Name the reactions of alkenes that may be used to introduce functional groups. PTS: 1 DIF: L1 REF: p. 735 Construct the general structure of an ether and describe how ethers are named. PTS: 1 DIF: L2 REF: p. 735 Construct the general structure of an ether and describe how ethers are named. PTS: 1 DIF: L1 REF: p. 738 Identify the structure of a carbonyl group as found in aldehydes and ketones. PTS: 1 DIF: L1 REF: p. 737 Identify the structure of a carbonyl group as found in aldehydes and ketones. PTS: 1 DIF: L1 REF: p. 737 Identify the structure of a carbonyl group as found in aldehydes and ketones. PTS: 1 DIF: L2 REF: p. 738 Identify the structure of a carbonyl group as found in aldehydes and ketones. PTS: 1 DIF: L1 REF: p. 740 Construct the general formula for carboxylic acids and explain how they are named. PTS: 1 DIF: L2 REF: p. 741 Describe an ester. PTS: 1 DIF: L1 REF: p. 743 | p. 744 Explain how dehydration is an oxidation reaction. SHORT ANSWER 109. ANS: 215 cal 4.184 = 9.00 10 J PTS: 1 DIF: L2 REF: p. 507 OBJ: 17.1.2 Classify processes as either exothermic or endothermic. 110. ANS: Heat energy = mass specific heat temperature change = 550 g 0.21 = 1.2 10 C cal PTS: 1 DIF: L2 REF: p. 508 OBJ: 17.1.3 Identify the units used to measure heat transfer. 111. ANS: T = Temperature change = = PTS: = 400 C 1 DIF: L2 REF: p. 508 OBJ: 17.1.3 Identify the units used to measure heat transfer. 112. ANS: T = 86.0 C – 19.0 C = 67.0 C specific heat = = = 9.31 10 PTS: 1 DIF: L2 REF: p. 509 | p. 510 OBJ: 17.1.3 Identify the units used to measure heat transfer. 113. ANS: H = 750 g 0.71 160 C = 85,000 J PTS: 1 DIF: L2 REF: p. 512 OBJ: 17.2.1 Describe how calorimeters are used to measure heat flow. 114. ANS: Specific heat = = 0.14 PTS: 1 DIF: L2 REF: p. 512 OBJ: 17.2.1 Describe how calorimeters are used to measure heat flow. 115. ANS: H= = 727 kJ/mol PTS: 1 DIF: L2 REF: OBJ: 17.2.2 Construct thermochemical equations. 116. ANS: 1.6 mol 30.2 kJ/mol = 48 kJ p. 517 PTS: 1 DIF: L2 REF: p. 521 OBJ: 17.3.1 Classify the enthalpy change that occurs when a substance melts, freezes, boils, condenses, or dissolves. 117. ANS: 50 g 0.48 3.0 C = 72 cal to raise the temperature of the solid to 27 C 50 g 45 cal/g = 2250 cal to melt the sample 2250 cal + 72 cal = 2322 cal 5000 cal – 2322 cal = 2678 cal remaining T= = 71 C 71 C + 27 C = 98 C The substance is in a liquid state. PTS: OBJ: 1 DIF: L3 REF: p. 521 17.3.1 Classify the enthalpy change that occurs when a substance melts, freezes, boils, condenses, or dissolves. 118. ANS: Heat to melt ice comes from heat released by the dissolving of NaOH. Amount of NaOH = 67 g H O = 0.050 mol NaOH PTS: 1 DIF: L3 REF: p. 520 | p. 521 OBJ: 17.3.2 Solve for the enthalpy change that occurs when a substance melts, freezes, boils, condenses, or dissolves. 119. ANS: Total heat = heat to melt ice + heat to warm water to 100 C + heat to evaporate water Total heat = (moles ice H ) + (moles water C T) + (moles water H ) 36 kJ = (moles of H O 6.0 kJ/mol) + (moles of H O 36 kJ = moles H O (6.0 kJ/mol + 0.0753 0.0753 100 C) + (moles of H O 100 C + 40.5 kJ/mol) 36 kJ = moles H O (54.0 kJ/mol) moles H O = moles H O = 0.67 mol PTS: 1 DIF: L3 REF: p. 527 OBJ: 17.4.1 State Hess's law of heat summation and describe how it is used in chemistry. 120. ANS: 2NO (g) N (g) + 2O (g) H = –67.7 kJ N (g) + 2O (g) N O (g) H = 9.7 kJ 2NO (g) N O (g) H = –58 kJ PTS: 1 DIF: L3 REF: p. 528 OBJ: 17.4.2 Solve for enthalpy changes by using Hess' law or standard heats of formation. 121. ANS: PTS: 1 DIF: L2 REF: p. 556 OBJ: 18.2.3 Explain what the value of Keq indicates about the position of equilibrium. 122. ANS: 10 M PTS: 1 DIF: L1 REF: p. 595 OBJ: 19.2.1 Describe how [H+] and [OH+] are related in an aqueous solution. 123. ANS: 1 10 mol/L PTS: 1 DIF: L2 REF: p. 595 | p. 596 OBJ: 19.2.1 Describe how [H+] and [OH+] are related in an aqueous solution. 124. ANS: K = [H ] [OH ] 40.5 kJ/mol) [H ] = = = 1 10 mol/L The solution is acidic. PTS: 1 DIF: L3 REF: p. 595 OBJ: 19.2.1 Describe how [H+] and [OH+] are related in an aqueous solution. 125. ANS: 10 M PTS: 1 DIF: L1 REF: p. 598 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 126. ANS: K = [H ] [OH ] [H ] = = =1 10- 2 mol/L pH = - log [H ] = - log [ 1 10- 2 mol/L] = 2.0 PTS: 1 DIF: L2 REF: p. 598 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 127. ANS: K = [H ] [OH ] [OH ] = = = 1 10- 1 mol/L pOH = log [OH ] = = 1.0 log [ 1 10- 1 mol/L] PTS: 1 DIF: L2 REF: p. 601 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 128. ANS: –log [H ] = pH = 3.7 log [H ] = –3.7 [H ] = antilog(–3.7) [H ] = 0.000 20M PTS: 1 DIF: L2 REF: p. 600 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 129. ANS: [HX] = 0.500M – 4.02 10 M = 0.496M K = = = 3.26 10 M PTS: 1 DIF: L3 REF: p. 607 OBJ: 19.3.2 Describe how an acid's strength is related to the value of its acid dissociation constant. 130. ANS: 3 10 PTS: 1 DIF: L2 REF: p. 607 OBJ: 19.3.2 Describe how an acid's strength is related to the value of its acid dissociation constant. 131. ANS: K = = = = 0.000 000 02 = 2 10 PTS: 1 DIF: L3 REF: p. 607 OBJ: 19.3.2 Describe how an acid's strength is related to the value of its acid dissociation constant. 132. ANS: PTS: 1 DIF: L2 REF: p. 737 OBJ: 23.3.1 Identify the structure of a carbonyl group as found in aldehydes and ketones. 133. ANS: CH CH CH COOH PTS: OBJ: 1 DIF: L3 REF: p. 744 | p. 745 23.3.4 Explain how dehydration is an oxidation reaction. NUMERIC RESPONSE 134. ANS: 7 PTS: 1 DIF: L1 REF: p. 596 | p. 597 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 135. ANS: 4 PTS: 1 DIF: L1 REF: p. 601 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 136. ANS: 10.0 PTS: 1 DIF: L1 REF: p. 601 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 137. ANS: 2.0 PTS: 1 DIF: L2 REF: p. 596 | p. 597 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 138. ANS: 2.2 PTS: 1 DIF: L2 REF: p. 597 | p. 598 OBJ: 19.2.2 Classify a solution as neutral, acid, or basic given the hydrogen-ion or hydroxide-ion concentration. 139. ANS: 80% PTS: OBJ: 1 DIF: L2 REF: p. 712 22.5.2 Describe the composition of natural gas and coal. ESSAY 140. ANS: Heat capacity is the quantity of heat required to change an object's temperature by 1 C. The heat capacity of any particular object varies with the mass of that object (as well as with the type of material in the object). The heat capacity of a steel girder is much greater than the heat capacity of a steel nail, for instance. Specific heat, on the other hand, does not vary with the mass of the object, but rather, depends only on the nature of the material in the object. Specific heat is the quantity of heat required to raise the temperature of 1 gram of a substance by 1 C. The specific heats of the steel in the steel girder and the steel in the steel nail are identical (assuming the two steels are of the same composition). Specific heat is a property of a particular material; heat capacity is a property of a particular object. PTS: 1 DIF: L3 REF: p. 508 OBJ: 17.1.3 Identify the units used to measure heat transfer. | 17.1.4 Distinguish between heat capacity and specific heat. 141. ANS: Generally a calorimeter consists of an insulated container, water, and a temperature-measuring instrument. The insulated container prevents heat from entering or leaving the system from the outside. There is water in the container to absorb heat. The temperature-measuring device is often a thermometer. Some calorimeters have a stirrer to distribute the heat evenly through the water. A bomb calorimeter may contain a set of ignition wires. PTS: 1 DIF: L3 REF: p. 511 | p. 512 OBJ: 17.2.1 Describe how calorimeters are used to measure heat flow. 142. ANS: Entropy is a measure of the degree of disorder in a system. A gas has more entropy than a liquid. A chemical reaction in which there are more molecules of product than molecules of reactant will cause an increase in entropy. A solution of sodium chloride in water has more entropy than a sodium chloride crystal. PTS: 1 DIF: L3 REF: p. 569 | p. 570 OBJ: 18.4.2 Describe the role of entropy in chemical reactions. 143. ANS: Both acids and bases are electrolytes; both cause indicators to change colors; and both react with each other to form water and a salt. Acids taste sour, while bases taste bitter. Bases feel slippery. Acids react with some metals to produce hydrogen gas. PTS: 1 DIF: L3 REF: p. 587 | p. 588 OBJ: 19.1.1 Define the properties of acids and bases. | 19.4.1 Define the products of an acid-base reaction. 144. ANS: According to the Brønsted-Lowry theory, acids donate protons to other substances, and bases accept protons from other substances. Ammonia accepts a proton from water and therefore acts as a Brønsted-Lowry base. The water donates the proton to ammonia and therefore acts as a Brønsted-Lowry acid. PTS: 1 DIF: L3 REF: p. 590 OBJ: 19.1.2 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and Lewis. 145. ANS: According to the Lewis theory, acids accept a pair of electrons to form a covalent, bond and bases donate an electron pair to form a covalent bond. The hydrogen ion accepts electrons from the hydroxide ion to make water. The hydrogen ion is the Lewis acid and the hydroxide ion is the Lewis base. PTS: 1 DIF: L3 REF: p. 592 OBJ: 19.1.2 Compare and contrast acids and bases as defined by the theories of Arrhenius, Brønsted-Lowry, and Lewis. 146. ANS: A strong acid ionizes completely and a concentrated acid dissolves well. The same is true for strong and concentrated bases. Ammonia is a weak base because it ionizes incompletely, but it can be concentrated because it dissolves well. PTS: 1 DIF: L3 REF: p. 609 OBJ: 19.3.1 Define strong acids and weak acids. 147. ANS: Because carbon has four valence electrons, each carbon atom can form four covalent bonds. Carbon-carbon bonds are quite stable, and this fact, coupled with carbon’s capacity to form four covalent bonds, allows carbon to form long straight or branched chains. Carbon atoms can also be joined in ring structures. Carbon can also form double and triple carbon-carbon bonds, which further increases the number of possible molecules. PTS: 1 DIF: L3 REF: p. 693 | p. 694 OBJ: 22.1.1 Describe the relationship between the valence electrons and bonding in carbon. 148. ANS: Unsaturated hydrocarbons have at least one double or triple carbon-carbon bond, and saturated hydrocarbons contain only single bonds. “Saturated” refers to the ratio of hydrogen atoms to carbon atoms. Molecules of a saturated hydrocarbon contain the maximum number of hydrogen atoms per carbon atom. PTS: 1 DIF: L3 REF: p. 702 OBJ: 22.2.1 Describe the difference between unsaturated and saturated hydrocarbons. 149. ANS: Geometric isomers have atoms joined in the same order, but differ in the orientation of groups around a double bond. For geometric isomers to exist, each carbon of the double bond must have at least one substituent. In the trans configuration, the substituted groups are on opposite sides of the double bond. In the cis configuration, the substituted groups are on the same side of the double bond. Examples are trans-2-butene and cis-2-butene. PTS: 1 DIF: L3 REF: p. 705 OBJ: 22.3.2 Describe the conditions under which geometric isomerism is possible. 150. ANS: Coal consists largely of condensed ring compounds of very high molecular mass. Due to the high proportion of these aromatic compounds in coal, the burning of this fuel produces more soot than does the burning of the more aliphatic fuels obtained from petroleum. In addition, the majority of the coal burned in North America contains about 7% sulfur, which produces the major pollutants SO and SO when it burns. PTS: 1 DIF: L3 REF: p. 715 OBJ: 22.5.2 Describe the composition of natural gas and coal. 151. ANS: A substitution reaction is an organic reaction in which an atom or group of atoms replaces another atom or group of atoms. An example of a replacement reaction is CH + Br CH Br + HBr. The halogen replaces the hydrogen because it is more reactive. PTS: OBJ: 1 DIF: L3 REF: p. 728 23.1.3 Describe how halocarbons can be prepared.