Ch 21 G12 CoreI- Choose the best answer, then transfer your answers to page (1) [32 marks; 2 each] 1. What characteristic do all aromatic hydrocarbons share? A. They all have a benzene ring structure in the molecule B. They all have the same molecular formula C. They all have carbon and hydrogen only D. They all have the same boiling point E. All the above 2. Which of the following is an aromatic compound? A. C 3H 6 B. C 5H 6 C. C 6H 6 D. C 6H 12 E. C 6H 14 3. Carcinogens are substances that cause to people who are exposed regularly to them. A. blindness B. cancer C. unconsciousness D. heart problems E. respiratory problems 4. Which of the following best compares the structural formula of cyclohexane with benzene?
A. Cyclohexane has six hydrogen atoms more than benzene B. Cyclohexane has six hydrogen atoms less than benzene C. All C-atoms in cyclohexane are bonded with three hydrogen atoms D. All C-atoms in benzene are bonded with two hydrogen atoms E. Both have the same general formula 5. From the diagram, what is the relationship between boiling point and molecular size (number of C-atoms) for hydrocarbons? A. There is no obvious relationship B. The smaller the molecule, the lower the boiling point C. The smaller the molecule, the higher the boiling point
D. The larger the molecule, the lower the boiling point E. All large molecules have the same boiling point 6. Which statement describes cracking process? A. It takes place in the presence of O 2 B. It takes place in the absence of a catalyst C. It produces starting materials to synthesize ammonia D. It produces starting materials to produce chemicals E. It converts heavier hydrocarbon fractions to gasoline 7. What do all organic compounds contain? A. Carbon B. Hydrogen C. Oxygen D. Water E. Nitrogen 8. Which structural formulas represent geometric isomers? I. II.
III. A. I and II only B. I and III only C. II and III only D. I, II, and III E. None of the above 9. What is the name of the compound whose skeletal formula is shown below? A. 2-butyl-2-ethylbutane B. 2,2,3-trimethylpentane C. 2,2,3-trimethyl-3-ethylpentane D. 3-ethyl-3,4,4-trimethylpentane E. 2,2-dimethy, 3-diethyl, 3-methylpropane 10. Which of the following compounds is alkene?
A. C 6H 6 B. C 6H 10 C. C 6H 12 D. C 6H 14 E. C 7H 16 11. What characteristic of carbon accounts for the large variety of hydrocarbon compounds? A. Carbon is able to form four strong ionic bonds with other elements B. Carbon is able to form eight strong covalent bonds with other elements C. Carbon is able to form four strong covalent bonds with other elements D. Carbon is able to form four strong hydrogen bonds with other elements E. Carbon is the most abundant element on earth 12. Which hydrocarbons are arranged in a ring in which carbon atoms form ONLY single bonds? A. Aromatic B. Cycloalkene C. Cycloalkyne D. Cycloalkane E. Alkane 13. Which model can be used to represent hydrocarbon molecules? I. Structural formula II. Molecular formula III. Space-filling A. I only
B. II only C. I and II only D. I and III only E. I, II, and III 14. Which of the following molecular substances has the lowest melting point? A. C 4H 4 B. C 4H 6 C. C 4H 8 D. C 4H 10 E. C 4H 12 15. The condensed structural formula for 1-butyne is. A. CH 3 C CCH 3 B. CH 2 CHCH 2CH 3 C. CH CCH 2CH 3 D. CH 3C CH E. CH CH(CH 2) 2CH 3 16. hat physical property of petroleum compounds is used to separate them during fractional distillation? A. Solubility in water B. Melting point
C. Density D. Molar mass E. Boiling point II- Answer the following questions. [52 marks] 17. Write the balanced chemical equations for the complete combustion of the following: (6 marks) a) ethyne b) butane 18. Draw TWO isomers for the following: a) Alkane with the molecular formula C 6 H 14. Show only the carbon chains. (4 marks)
b) The structures of -3-hexene ( cis- and trans-). (4 marks) 19. Complete the following table to contrast between saturated and unsaturated hydrocarbons. (12 marks; 2 each) Saturated Hydrocarbon Unsaturated Hydrocarbon Carbon-Carbon bond Solubility in water Boiling point
20. Name the structures shown using IUPAC rules. (12 marks; 2 each) a) b) Name c) d) Name e) f) Br Name Draw the structural formula for each of the following. (14 marks; 2 each) 1,2-dichloroethene
1,1,2,-trimethylcyclohexane 1,2-dimethylcyclopropane 2-methyl-1-propene a. benzene b. 2,2-dimethyl-3-hexyne
c. 2-bromo-1-propene III-Answer the following questions. [16 marks] 22. Explain why benzene is NOT considered as an alkene with several bonds. (3 marks) 23. Do the following structural formulas represent the same molecule? Explain. (4 marks)
24. Which is more reactive; 2-propene or 2-propyne? Explain. (3 marks) 25. Name two natural resources of hydrocarbons. (3 marks; 1.5 each) 26. What happens when you try to dissolve butane in water? Explain. (3 marks) I-Choose the best answer. [6marks 1. Which model can be used to represent hydrocarbon molecules? A. Ball and stick B. Molecular formula C. Space- filling D. Structural formula E. All the above 2. What is the main characteristic of organic compounds? A. They all contain carbon and hydrogen atoms B. They all contain carbon
C. They all have high boiling point D. They all exist in liquid state E. They all occurred naturally 3. The general formula of alkanes is. A. C nh 2n+1 B. C nh 2n-2 C. CnHn+2 D. C nh 2n E. C nh 2n+2 4. Which bond arrangement describes how many electrons are shared between the TWO carbon atoms in hydrocarbon compounds? Fig. III Fig. I Fig. II A. Fig I only B. Fig II only C. Fig III only D. Fig II and Fig III only E. Figures I, II, and III 5. The process of fractional distillation involves boiling crude oil in order to. A. increase its stored energy B. separate it into its usable components C. create petroleum oil D. change its viscosity
E. produce natural gas 6. Which statement describes cracking process? A. It converts heavier fractions to gasoline B. It takes place in the absence of O 2 and in the presence of a catalyst C. It produces starting materials to synthesize plastic products D. It produces starting materials to produce synthetic fabrics E. All the above II. Answer the following questions. [ 14 marks] 7. Give the IUPAC name of the following structures. (1mark each) Cl
Br 8. Draw the condensed structural formulas for: (1mark each) a. 2-chloro-3-methyl cyclopropane b. 1,2,3-trichloromethane
c. Methylcyclohexane 9. Write the condensed formula of an alkane having 4 carbon atoms. (1mark) 10. What happens when you try to dissolve butane in water? Explain your answer. (1mark) 11. Referring to the table below, although the molecular mass of water is close to the molecular mass of methane, how would you explain the great difference in boiling points of methane and water? (2marks) Comparing Physical properties Substance and formula Water [ H2O ] Methane [ CH4 ] Molecular mass 18 amu 16 amu State at room temperature Liquid gas Boiling point 100 C 162 C Melting point 0 C 182 C
12. Name two natural resources of hydrocarbons. (2marks; 1each) 13. What characteristic of carbon accounts for the large variety of organic compounds? (1mark) True/False Indicate whether the statement is true or false. 1. Saturated hydrocarbons react with bromine. 2. Homologs have the same molecular formula. 3. Geometric isomers have only single bonds. 4. A branched hydrocarbon has at least one branch of carbon atoms extending from the parent chain. 5. Propyne is less reactive than propane. 6. Optical isomers have at least one chiral carbon atom. 7. An isobutane has a carbon branch atom extending from the second carbon atom of the chain.
8. Sunflower oil reacts with bromine and therefore contains saturated hydrocarbons. 9. L-glucose and D-glucose are isomers of each other. 10. Cyclopropane is a hydrocarbon that has three carbons in a straight chain. 11. Straight chain hydrocarbons do not have the prefix, cyclo, since all the carbons atoms are in the form of a straight chain. 12. The molecular formula of optical isomers are the same. 13. The use of the prefix di indicates the presence of two substituents of the same type. 14. Substances that can cause cancer are called carcinogens. 15. The aromatic compound formed as a by-product of burning wood and coal and which causes cancer of the scrotum is benzopyrene. 16. An optically active compound has an asymmetric atom. 17. Alkanes are compounds with carbon and hydrogen joined by double or triple bonds. 18. Alkanes are the simplest types of hydrocarbons. 19. The isobutane given below is an example of a branched-chain hydrocarbon. 20. The IUPAC name of is 2-ethyl butane.
21. The structure of 3-ethyl-2,2,3,4-tetramethylpentane is. 22. Cyclohexane is a cyclic hydrocarbon having six carbon atoms in a straight chain. 23. Sunflower oil is a vegetable oil that reacts with bromine. Therefore, it contains unsaturated hydrocarbons. 24. Propyne is more reactive than propane. 25. The IUPAC name of is 3-methyl-3-hexene. 26. D-glucose and L-glucose are optical isomers. Multiple Choice Identify the choice that best completes the statement or answers the question. 27. have double bonds. a. alkanes c. alkynes b. alkenes d. metals 28. have single bonds. a. alkanes c. alkynes b. alkenes d. metals 29. Which of the following is NOT an isomer of hexane? a. 2-methylpentane c. 2,3-dimethylbutane b. 2,2-dimethylbutane d. 2-methyl-2-ethylbutane 30. bonds are formed by the transfer of electrons. a. ionic c. nonpolar b. polar d. metallic 31. How are 3-methylheptane,3,3-dimethylhexane and 2-ethyl-4-methylpentane related to each other? a. They are homologous. c. They are optical isomers. b. They are structural isomers. d. They are geometric isomers.
32. The covalent bond in alkanes is: a. ionic c. nonpolar b. polar d. metallic 33. bonds are found in metals only. a. ionic c. nonpolar b. polar d. metallic 34. covalent bonds are formed in compounds in which the difference in electronegativity is high. a. ionic c. nonpolar b. polar d. metallic 35. have triple bonds. a. alkanes c. alkynes b. alkenes d. metals 36. Which compound has an asymmetric carbon atom? a. 2,2-dimethylpentane c. 1-hexane b. 2,3,4-trimethylhexane d. 2,2-dimethylpropane 37. In trans-3-hexene, two ethyl groups are on the side(s) of the double bond. a. same c. opposite b. different d. lateral 38. The number of different groups attached to an asymmetric carbon is. a. 1 c. 3 b. 2 d. 4 39. In aromatic compounds, the position of the double bond is. a. fixed c. vertical b. not fixed d. horizontal 40. The molecular formals of hydrocarbons in a gasoline fraction range from C 5H 12 to: a. C 6H 14 c. C 10H 22 b. C 8H 18 d. C 12H 26 41. The molecular formula of octane is: a. C 2H 6 c. C 6H 14 b. C 4H 10 d. C 8H 18 42. Which compound would show geometrical isomerism to the structure shown?
a. 1-pentane c. 3-methylbutane b. 3-methyl-1-butyne d. 2-pentane 43. How many electrons are shared between carbon atoms in ethene? a. 1 c. 3 b. 2 d. 4 44. How many electrons are shared between carbon atoms in ethyne? a. 1 c. 3 b. 2 d. 4 45. The general formula for is C nh 2n. a. alkanes c. alkynes b. alkenes d. aromatic compounds 46. The correct IUPAC name of the compound is. a. 3,4-dimethylpentane c. 2,3-dimethylpentane b. 2,3-dimethylbutane d. 2,2,3-dimethylbutane 47. The structure of 3-ethyl-5,7-dimethyl-5-propylnonane is. a.
b. c. d. 48. Name the cycloalkane given below. a. 1,2,4-trimethylcyclohexane c. 1,2,4-trimethylcyclopentane b. 1,2,4-dimethylcyclopentane d. 1,3,5-trimethylcyclopentane
49. The correct structural formula of 1,2-diethyl-2,3-dimethyl-6-propylcyclooctane is. a. b. c. d. 50. What is the nature of a covalent bond in alkanes? a. Ionic c. Nonpolar covalent b. Polar covalent d. Metallic 51. The correct condensed structure of a compound having the IUPAC name 6-ethyl-6,7-dimethyl-2,4-dioctyne is. a.
b. c. d. 52. Which is NOT an isomer of hexane? a. 2-methylpentane c. 2,3-dimethylbutane b. 2,2-dimethylbutane d. 2-methyl-2-ethylbutane 53. How are 3-methylheptane,3,3-dimethylhexane and 2-ethyl-4-methylpentane related to each other? a. They are geometric isomers. c. They are structural isomers. b. They are homologous. d. They are optical isomers. 54. Which compound would show geometrical isomerism? a. 1-pentene c. 3-methylbutane b. 3-methyl-1-butyne d. 2-pentene 55. Which compound has an asymmetric carbon atom? a. 2,2-dimethylpentane c. 1-hexane b. 2,3,4-trimethylhexane d. 2,2-dimethylpropane Completion Complete each statement. 56. The structure of 3-ethyl-4-methylhexane is. 57. The IUPAC name of a compound represented by the line structure is.
58. The IUPAC name of is. 59. In trans-3-hexene, two ethyl groups are on the sides of the double bond. 60. The number of different groups attached to an asymmetric carbon atom is. 61. In aromatic compounds, the position of the double bond is. 62. The IUPAC name of is. 63. Substances that can cause cancer are called. 64. The IUPAC name of the aromatic compound formed as a by-product of the burning wood and coal and which causes cancer of the scrotum is. 65. The molecular formulas of hydrocarbons in a gasoline fraction range from to. 66. The molecular formula of octane is. Short Answer 67. Give the IUPCA name for the following structure. 68. Give the IUPAC name of the following structure.
69. Give the IUPAC name of the following structure. 70. Name the cycloalkane. 71. What is the IUPAC name of the represented compound? 72. Give the IUPAC name of the following structure. 73. Identify the class of hydrocarbons to which the following structure belongs.
74. Is the given compound optically active or optically inactive? 75. Is the given compound a cis- or trans- isomer? 76. What is the IUPAC name of the following compound? 77. Write the molecular formula of an alkane having five carbons atoms. 78. Write the condensed structural formula of an alkane having five carbon atoms. 79. Describe why butane is used as a domestic fuel. 80. Use line structures to draw the condensed structural formulas for: a. 1-ethyl-2,3-dimethylcyclopropane
b. 1,2-diethyl-1-methylcyclobutane c. 3,5-diethyl-2,2-dimethyl-1-propylcyclohexane 81. Alkenes are hydrocarbons which are represented by the general formula. Write the molecular formula of an alkene that has four carbon atoms. Draw all the isomers possible by this formula and write the IUPAC name of all the isomers. 82. Determine the total number of asymmetric carbon atom(s) present in the compound given below. Problem 83. Write the IUPAC name of the following structure:
84. Draw the structure of 3,4,6-triethyl-5-methyloctane. 85. How many electrons are shared between the carbon atoms in ethene and ethyne? Draw their Lewis structures and calculate. 86. a. Find the molecular formula of alkenes having five and eight carbon atoms. b. Write the condensed structural formulas for these alkenes by putting a double bond between the first and second carbon atom of the longest carbon atom chain. 87. A hydrocarbon has a formula. Identify the class of hydrocarbons to which it belongs. Also draw its condensed structural formula. If it is an alkene or an alkyne, use the double or triple bond at the first carbon of the longest chain.
88. Draw the structure of the compounds: a. 3,4-dimethyl-1-cyclobutene b. 3-ethyl-2,4,6,8-tetramethyl-5-propyl-2,4,6-trinonene 89. Label the given compound as optically active or optically inactive. J Z C T E 90. Write the IUPAC name of the following compound: 91. Determine whether the given compound is a cis-or trans-isomer. F F
A A 92. Determine the IUPAC name of the following structure: Essay 93. Alkanes are compounds of carbon and hydrogen. a Write the molecular formula of an alkane having five carbon atoms. b Write the condensed structural formula of an alkane having five carbon atoms. c Write all of the structural formulas of branched-chain alkane with the molecular formula from part a.
94. The alkanes are the simplest types of hydrocarbons. a Why is butane used as a domestic fuel? b What happens when you try to dissolve butane in water? c Why is butane less reactive in nature? 95. Alkane, alkene, and alkyne are various types of hydrocarbons. a Separate the alkanes, alkenes, and alkynes from the following list: b Name the hydrocarbon that burns with oxygen and is used in welding. c Which hydrocarbon is used in the manufacture of plastic and artificial ripening of food? 96. Petroleum is the main source of aromatic and aliphatic hydrocarbons. a. What is fractional distillation? b. How is cracking done?
I-Choose the best answer [7.5 marks, 1.5 1. Which model can be used to represent hydrocarbon molecules? A. Ball and stick B. Molecular formula C. Space- filling D. All the above
2. What is the main characteristic of organic compounds? A. They all contain carbon C. They all have high boiling point D. They all exist in liquid state E. They all occurred naturally 3. The general formula of alkanes is _. A. CnH2n+1 B. CnH2n-2 C. CnHn+2 D. CnH2n+2
T2 Chemistry Project G12 Core 4. Which bond arrangement describes how many electrons are shared between the TWO Carbon atoms in hydrocarbon compounds? Fig. II Fig. I Fig. III A. Fig I only B. Fig II only C. Fig III only D. Figures I, II, and III 5. The process of fractional distillation involves boiling crude oil in order to. A. increase its stored energy B. separate it into its usable components C. create petroleum oil D. change its viscosity II- Solve the following problems: 1. Write the condensed formula of an alkane having 4 carbon atoms. [2marks]
T2 Chemistry Project G12 Core 2. Name two natural resources of hydrocarbons. [2 mark] 3. Explain why carbon can form many organic compounds? [1.5 marks] III-Answer the following questions A. Draw the structural formula of each of the following alkanes: [2 marks] a. C 6H 12 b. Heptane
T2 Chemistry Project G12 Core B. Compare between saturated and unsaturated hydrocarbons. [2 marks] Saturated Unsaturated C. Write the name of the following hydrocarbons. [2 marks] 1. 2....