MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Transcription

1 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) All of the following statements are general properties of organic compounds except The bonds are covalent. They have limited or no water solubility. C) They have relatively low melting points. D) They have relatively low boiling points. E) They usually behave as electrolytes in solution. 1) 2) Which of the statements about the behavior of the element carbon in organic molecules is incorrect? 2) Carbon can be involved in polar covalent bonds. Carbon can form single, double, or triple bonds with other carbon atoms. C) In addition to other carbon atoms, carbon is likely to form bonds with hydrogen, nitrogen, or oxygen. D) When carbon forms four single bonds, the bond angles are 90. E) Carbon always forms four bonds. 3) Which atom is least likely to form a polar covalent bond with carbon? H N C) Cl D) O E) F 3) 4) Which atom is most likely to form a polar covalent bond with carbon? O C C) H D) S E) Na 4) SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 5) Describe the unique characteristics of carbon that make it the basis of such a large number of organic compounds. 5) MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 6) Which family of organic molecules is a hydrocarbon? aromatic aldehyde C) alcohol D) amide E) amine 6) 7) Which functional group does not contain oxygen? ketone alcohol C) carboxylic acid D) ester E) amine 7) 1

2 8) The functional group illustrated by R O Rʹ is an ether. alcohol. C) aldehyde. D) ester. E) alkyl. 8) 9) The functional group illustrated by R OH is an ester. alcohol. C) alkyl. D) aldehyde. E) ether. 9) 10) The functional group illustrated below is an 10) ether. ester. C) amide. D) amine. E) alcohol. 11) The functional group illustrated below is an 11) ether. alcohol. C) ester. D) alkyl. E) aldehyde. 12) The functional group which illustrates an ester is. R C C Rʹ 12) C) R C NH2 D) E) 13) Which of the following statements about alkyl groups is incorrect? -C2H5 is an example. 13) An alkyl group with four carbon atoms would include butyl in its name. C) They are derived from alkenes. D) In naming, they are used as prefixes and have a ʺylʺ ending. E) none of the above 2

3 14) The family of organic compounds with functional groups that do not consist only of hydrocarbons is 14) arenes. aldehydes. C) alkanes. D) alkynes. E) alkenes. 15) All of the families below include functional groups which contain oxygen except esters. ethers. C) ketones. D) alkyl halides. E) carboxylic acids. 15) 16) Which factor is most important in determining the chemistry of an organic molecule? the number of carbon-hydrogen bonds the functional groups C) the number of carbon-carbon bonds D) the number of branches in the carbon chain E) the melting point 16) 17) Which family of organic compounds does not contain any multiple bonds? alkyl halides aldehydes C) alkynes D) ketones E) alkenes 17) 18) The arene or aromatic functional group is often represented as at least one double bond between carbon and oxygen. a carbon-oxygen-hydrogen group. C) a six-membered ring with three double bonds. D) one or more bonds between carbon and nitrogen. E) a carbon-carbon triple bond. 18) 3

4 19) The alkyne functional group is one or more bonds between carbon and nitrogen. a six-membered ring with three double bonds. C) a double bond between carbon and oxygen. D) a carbon-carbon triple bond. E) a carbon-oxygen-hydrogen group. 19) 20) The alcohol functional group is a carbon-oxygen-hydrogen group. one or more bonds between carbon and nitrogen. C) a carbon-carbon triple bond. D) a six-membered ring with three double bonds. E) a double bond between carbon and oxygen. 20) 21) Which list includes all the elements that would be found in an alkane with an amine group? C, H, O C, H, N C) H, N D) C, H E) C, H, O, H 21) SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 22) Explain the term ʺfunctional group.ʺ How do organic chemists use the functional group concept? 22) MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 23) Two or more compounds with the same molecular formula but with the atoms connected differently are referred to as 23) constitutional isomers. conformations. C) normal alkanes. D) branched alkanes. E) functional groups. 24) In straight-chain alkanes, the carbon atoms on each end of the molecule always form bonds with atoms of hydrogen; the carbons within the molecule always form bonds with hydrogen atoms. 24) 2; 2 4; 4 C) 3; 2 D) 4; 2 E) 3; 3 25) How many structural isomers are possible for the molecular formula, C4H10? 25) 2 1 C) 4 D) 3 E) 5 4

5 26) Which molecule is an isomer of the molecule shown? 26) C) D) E) CH3(CH2)4CH3 27) Which molecule is not an isomer of the molecule shown? 27) C2H5 O C2H5 C) CH3 O CH2CH2CH3 D) E) C4H9OH 5

6 28) All of the choices listed are representations of the same molecule except 28) C) CH3CH2CH2CH2CH3. D) (CH3)2CHCH2CH3. E) C5H12. 29) The carbon skeleton of an alkane is shown below. How many hydrogen atoms are bonded to the carbon marked with a *? 29) 0 1 C) 2 D) 3 E) 4 30) The carbon skeleton of an alkane is shown below. How many hydrogen atoms are bonded to the carbon marked with a *? 30) 0 1 C) 2 D) 3 E) 4 31) All of the following are representations of the same molecule except. 31) cyclobutane CH2CH2CH2CH2 C) C4H8 D) 6

7 32) The various shapes taken on by an organic molecule are known as configurations constitutional isomers C) conformations D) preferential isomers E) none of the above 32) 33) How many carbon atoms are there in the longest continuous chain of the molecule shown? 33) (CH3)3C (CH2)3 CH3 8 3 C) 6 D) 4 E) cannot be determined without additional information 34) The name of the hydrocarbon with three carbon atoms and having only single bonds between carbon atoms is 34) propane. ethane. C) butane. D) decane. E) methane. 35) The carbon atom marked with * is a carbon atom. 35) tertiary secondary C) quaternary D) primary E) none of these 36) The carbon atom marked with * is a carbon atom. 36) secondary primary C) quaternary D) tertiary E) none of these 7

8 37) The carbon skeleton of an alkane is shown below. How many hydrogen atoms are bonded to the carbon marked with a *? 37) 0 1 C) 2 D) 3 E) 4 38) The carbon atom marked with * is a carbon atom. 38) primary tertiary C) secondary D) quaternary E) none of these 39) How many carbon atoms are there in the longest continuous chain of the molecule shown? 39) (CH3)2CH (CH2)5 CH3 5 9 C) 8 D) 7 E) cannot be determined without additional information 8

9 40) The condensed structure of 2,4-dimethyl-heptane is 40) C) D) E) CH3CH3CH2CH3CH2CH2CH2CH3 41) The condensed structure of 2,4-dimethyl-hexane is 41) C) D) E) CH3CH3CH2CH3CH2CH2CH2CH3 9

10 42) The condensed structure of 2,4-dimethyl-octane is 42) C) D) E) CH3CH3CH2CH3CH2CH2CH2CH3 43) The condensed structure of n-octane is 43) C) D) E) CH3CH3CH2CH3CH2CH2CH2CH3 10

11 44) The condensed structure of 2,2,4,4-tetramethyl-heptane is 44) CH3CH3CH2CH3CH2CH2CH2CH3 C) D) E) 45) What is the IUPAC name of the compound shown? 45) (CH3)3 C CH2 CH2 CH3 2,2-dimethylpentane heptane C) 2-dimethylpentane D) 2-ethylhexane E) 1,1,1-trimethylbutane 46) What is the IUPAC name of the compound shown? 46) 2,4,5-trimethylheptane 3,4,6-trimethylheptane C) 2-ethyl-3,5-dimethylhexane D) 5-ethyl-2,4-dimethylhexane E) 3,5-dimethyl-2-ethylhexane 11

12 47) What is the IUPAC name of the compound shown? 47) 4,6-dimethyloctane 4-methyl-2-ethylheptane C) 6-ethyl-4-methylheptane D) 2-ethyl-4-methylheptane E) 3,5-dimethyloctane 48) What is the IUPAC name of the compound shown? 48) 4-isopropyldecane 3-hexyl-2-methylhexane C) 4-isobutyldecane D) 4-propyldecane E) 4-sec-butyldecane 49) What is the IUPAC name of the compound shown? 49) isohexane dimethylbutane C) ethylmethylpropane D) 2,2-dimethylbutane E) hexane 50) What is the minimum number of carbons that must be present in a molecule to have a secondary carbon? 50) 1 4 C) 2 D) 5 E) 3 12

13 51) The molecule shown is named as a substituted because. 51) decane; it contains 10 atoms of carbon. butane; four carbons are substituted onto the chain. C) hexamethane; it contains six methyl groups altogether. D) tetramethane; it contains four methyl groups as branches. E) hexane; it contains six atoms of carbon in its longest chain. 52) In the molecule 3,3-dimethylhexane, carbon number two is primary. quaternary. C) tertiary. D) secondary. E) none of the above 52) 53) Which group is the best description of the properties of alkanes? flammable, reactive, water soluble flammable, non-reactive, insoluble in water C) non-flammable, non-polar, water soluble D) non-flammable, polar, reactive E) none of the above 53) 54) What is the IUPAC name of the compound shown? 54) isooctane 3,3-dimethylhexane C) 2-ethyl-2-methylpentane D) 2,2-ethyl-methylpentane E) 2-methyl-2-propylbutane 13

14 55) Which of the following properties is not characteristic of alkanes? They form strong hydrogen bonds. They are generally less dense than water. C) Their melting points increase with molecular weight. D) They are tasteless and colorless. E) They are nontoxic. 55) 56) Which is not a property of most alkanes? light odor soluble in water C) burn readily in an open flame D) colorless E) they are all properties of alkanes 56) 57) Which substance is not reactive with respect to alkanes? 57) Br2 O2 C) H2 D) Cl2 E) none of the above 58) When hydrocarbons undergo complete combustion, the product(s) is(are) CO2 and H2O. 58) H2O and O2. C) H2O. D) CO2 and O2. E) CO2. 59) Monochlorination of Pentane, C5 H12, leads to formation of how many different products? 59) 2 4 C) 3 D) 1 E) 5 14

15 60) When an alkane reacts with an element from group 7A, the reaction is referred to as decomposition. displacement. C) oxidation. D) halogenation. E) combustion. 60) 61) What is the IUPAC name of the molecule shown? 61) cyclohexane 1,2-dimethylcyclobutane C) 3,4-dimethylcyclobutane D) dimethylcyclobutane E) 2,3-dimethylcyclobutane 62) What is the IUPAC name of the molecule shown? 62) dimethylcyclobutane 1,2-dimethylcyclobutane C) cyclohexane D) 2,2-dimethylcyclobutane E) 1,1-dimethylcyclobutane 63) How many hydrogen atoms are present in the molecule shown? 63) C) 6 D) 12 E) 18 64) How many hydrogens are present in a molecule composed of a six membered ring of carbon atoms and no double or triple bonds? 64) C) 14 D) 16 E) 12 15

16 MATCHING. Choose the item in column 2 that best matches each item in column 1. Match the name of the functional group with the molecule which correctly illustrates it. 65) amine 65) 66) carboxylic acid 66) 67) alkyl halide 68) ketone 67) 68) 69) alcohol 70) ester C) 69) 70) 71) arene (aromatic) 71) D) E) F) G) CH3CH2Br 16

17 72) aldehyde 72) 73) amide 73) 74) ether 74) C) CH3CH2 O CH2CH3 17

18 Answer Key Testname: UNTITLED11 1) E 2) D 3) A 4) A 5) It has four valence electrons and is a very small atom, so it always forms four strong covalent bonds. It bonds with other carbon atoms to form long chains or rings. 6) A 7) E 8) A 9) B 10) C 11) E 12) E 13) C 14) B 15) D 16) B 17) A 18) C 19) D 20) A 21) B 22) A functional group is a group of atoms within a larger molecule that gives the molecule specific physical and chemical properties. Organic chemists use functional groups as an organizational tool in classifying, naming, and predicting the properties of organic molecules. 23) A 24) C 25) D 26) A 27) B 28) D 29) B 30) D 31) B 32) C 33) C 34) A 35) A 36) B 37) A 38) D 39) C 40) A 41) A 42) A 43) E 44) D 45) A 46) A 47) E 18

19 Answer Key Testname: UNTITLED11 48) A 49) D 50) E 51) E 52) D 53) B 54) B 55) A 56) B 57) C 58) A 59) C 60) D 61) B 62) E 63) D 64) E 65) A 66) F 67) G 68) C 69) B 70) E 71) D 72) A 73) B 74) C 19