OChem CH 12-13

All of the following are general properties of alkenes except A) less reactive than the corresponding alkanes. B) soluble in non-polar (organic) solvents. C) flammable. D) may exist as cis-trans isomers. E) low boiling points.

A

Chemical reactions involving double bonds are generally referred to as ________ reactions. A) addition B) oxidation C) combustion D) substitution E) reduction

A

Ethylene and acetylene are the common names for the molecules ________ and ________, respectively. A) C2H4 and C2H2 B) C2H6 and C3H8 C) C2H4 and C3H6 D) C2H2 and C2H6 E) C2H4 and C2H6

A

In organic chemistry, the term unsaturated means a molecule A) which contains one or more multiple bonds between carbon atoms. B) which can react by taking up one or more water molecules. C) which is formed from many smaller molecules. D) which has the maximum number of carbon-hydrogen bonds possible. E) with a specific six-membered ring structure.

A

The alcohol functional group is A) a carbon-oxygen-hydrogen group. B) 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.

A

The bond angle about a carbon atom involved in a double bond is A) 120°. B) 109.5°. C) 105°. D) 90°. E) 180°

A

The functional group illustrated by R-O-Rʹ is an A) ether. B) alcohol. C) aldehyde. D) ester. E) alkyl.

A

The monomer unit used to produce polypropylene is A) CH2-CH2-CH3. B) CH3-CH2-CH2-CH3. C) CH2-CH2-CH2Cl. D) CH2-CH2. E) CHCl-CH2

A

The name of the hydrocarbon with three carbon atoms and having only single bonds between carbon atoms is A) propane. B) ethane. C) butane. D) decane. E) methane

A

The name of the polymer formed from CH2CH2 is A) polyethylene. B) polystyrene. C) polyvinyl chloride. D) polypropylene. E) none of the above

A

The organic chemical produced in the largest quantities in the U.S. is A) ethylene B) benzene. C) octane. D) polyethylene. E) sulfuric acid.

A

The term used to describe the geometry of a carbon atom involved in a triple bond is A) linear. B) perpendicular. C) distorted tetrahedral. D) trigonal planar. E) tetrahedral.

A

Two or more compounds with the same molecular formula but with the atoms connected differently are referred to as A) constitutional isomers. B) conformations. C) normal alkanes. D) branched alkanes. E) functional groups.

A

What is the IUPAC name of the compound shown? (CH3)3-C-CH2-CH2-CH3 A) 2,2-dimethylpentane B) heptane C) 2-dimethylpentane D) 2-ethylhexane E) 1,1,1-trimethylbutane

A

When 2-butene reacts completely with bromine, the product is A) 2,3-dibromobutane. B) 2-bromobutane. C) 3-bromobutane. D) 1,2-dibromobutane. E) 1,3-dibromobutane.

A

When hydrocarbons undergo complete combustion, the product(s) is(are) A) CO2 and H2O. B) H2O and O2. C) H2O. D) CO2 and O2. E) CO2

A

Which atom is least likely to form a polar covalent bond with carbon? A) H B) N C) Cl D) O E) F

A

Which atom is most likely to form a polar covalent bond with carbon? A) O B) C C) H D) S E) Na

A

Which family of organic compounds does not contain any multiple bonds? A) alkyl halides B) aldehydes C) alkynes D) ketones E) alkenes

A

Which family of organic molecules is a hydrocarbon? A) aromatic B) aldehyde C) alcohol D) amide E) amine

A

Which of the following properties is not characteristic of alkanes? A) They form strong hydrogen bonds. B) 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.

A

An addition reaction can best be described as a reaction in which A) a single reactant undergoes reorganization of its chemical bonds, producing an isomer of the reactant. B) two reactants combine to form one new product with no extra atoms. C) a hydrogen reacts with oxygen to produce CO2, H2O, and energy. D) a single reactant splits into two products. E) two reactants exchange atoms to give two new products

B

The bond angle about a carbon atom involved in a triple bond is A) 105°. B) 180°. C) 120°. D) 90°. E) 109.5°

B

The family of organic compounds with functional groups that do not consist only of hydrocarbons is A) arenes. B) aldehydes. C) alkanes. D) alkynes. E) alkenes.

B

The functional group illustrated by R-OH is an A) ester. B) alcohol. C) alkyl. D) aldehyde. E) ether.

B

The process used to produce simple alkenes is A) condensation of small molecules. B) cracking of alkanes. C) distillation of crude oil. D) polymerization of monomers. E) smelting of ores.

B

The term used to describe the geometry of a carbon atom involved in a double bond is A) linear. B) trigonal planar. C) perpendicular. D) tetrahedral. E) distorted tetrahedral.

B

What is the IUPAC name of the molecule shown? CH2=CH-CH=CH2 A) 1,4-butadiene B) 1,1-butadiene C) diethylene D) 1,3-butadiene E) 1,2-butadiene

B

Which group is the best description of the properties of alkanes? A) flammable, reactive, water soluble B) flammable, non-reactive, insoluble in water C) non-flammable, non-polar, water soluble D) non-flammable, polar, reactive E) none of the above

B

Which is not a property of most alkanes? A) light odor B) soluble in water C) burn readily in an open flame D) colorless E) they are all properties of alkanes

B

Which list includes all the elements that would be found in an alkane with an amine group? A) C, H, O B) C, H, N C) H, N D) C, H E) C, H, O, H

B

Which molecule can have cis-trans isomers? A) (CH3)2C=CHCH3 B) CH3CH=CHCl C) (CH3)2C=C(CH3)2 D) CH3CH=C(CH3)2 E) CH3CH=CCl2

B

Which molecule represents 4-ethyl-2-hexyne? A) (CH3CH2)2CHC≡CCH(CH2CH3)2 B) (CH3CH2)2CHC≡CCH3 C) CH3CH2C≡CCH2CH2CH3 D) CH3CH2CH2C≡CCH3 E) CH3CH2CH2CH2C≡CCH3

B

Which phrase most accurately describes the structure common to all aromatic compounds? A) a ring described as 1,3,5-hexatriene B) identical bonds between all 6 carbon atoms, with 6 electrons moving freely C) a six-membered ring with easily broken carbon-carbon bonds D) a six-membered ring with 3 double and 3 single bonds E) none of the above

B

A rearrangement reaction can best be described as a reaction in which A) a single reactant splits into two products. B) a hydrocarbon reacts with oxygen to produce CO2, H2O, and energy. C) a single reactant undergoes reorganization of its chemical bonds, producing an isomer of the reactant. D) two reactants combine to form one new product with no extra atoms. E) two reactants exchange atoms to give two new products.

C

According to Markovnikov's rule, when HCl reacts with the molecule shown, which product will result? (CH3)2C=CHCH3 + HCl → ????? A) (CH3)2CH-CH2CH2Cl B) (CH3)2CCl-CHClCH3 C) (CH3)2CCl-CH2CH3 D) Cl2CH-CHClCH3 E) (CH3)2CH-CHClCH3

C

Alkenes and simple aromatics are similar in all of the following properties except A) nonpolarity. B) insolubility in water. C) lack of toxicity. D) solubility in non-polar solvents. E) flammability

C

All of the following are examples of addition reactions of alkenes except A) chlorination. B) hydration. C) oxidation. D) hydrogenation. E) bromination.

C

An elimination reaction can best be described as a reaction in which A) two reactants combine to form one new product with no extra atoms. B) a hydrocarbon reacts with oxygen to produce CO2, H2O, and energy. C) a single reactant splits into two products. D) a single reactant undergoes reorganization of its chemical bonds, producing an isomer of the reactant. E) two reactants exchange atoms to give two new products.

C

Bromobenzene can be prepared from benzene by reaction with ________ A) HBr B) Br2 C) Br2 and FeBr3 D) HBr and H20 E) Br2 and KBr

C

Cis-trans isomerism occurs when A) a branched alkane has a halogen added to two adjacent carbon atoms. B) hydrogen is added to both of the carbon atoms in a double bond. C) the carbons in an alkene double bond each have two different substituent groups. D) the carbons in the para position of an aromatic have the same substituent groups. E) an alkene is hydrated according to Markovnikov's Rule.

C

How many carbon atoms are there in the longest continuous chain of the molecule shown? (CH3)2CH-CH2)5-CH3 A) 5 B) 9 C) 8 D) 7 E) cannot be determined without additional information

C

How many carbon atoms are there in the longest continuous chain of the molecule shown? (CH3)3C(CH2)3CH3 A) 8 B) 3 C) 6 D) 4 E) cannot be determined without additional information

C

How many hydrogen atoms are contained in a molecule of cyclopentene? A) 12 B) 5 C) 8 D) 6 E) 10

C

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. A) 2; 2 B) 4; 4 C) 3; 2 D) 4; 2 E) 3; 3

C

Monochlorination of Pentane, C5 H12 , leads to formation of how many different products? A) 2 B) 4 C) 3 D) 1 E) 5

C

The arene or aromatic functional group is often represented as A) at least one double bond between carbon and oxygen. B) 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.

C

The concept that explains the properties of aromatic compounds based on a structure that is an average among two possible structures is A) double bonding. B) oxidation. C) resonance. D) polymerization. E) cis-trans isomerism.

C

The various shapes taken on by an organic molecule are known as ________ A) configurations B) constitutional isomers C) conformations D) preferential isomers E) none of the above

C

What is the ideal angle between the H-C-C bond in ethylene? A) 109.5° B) 180° C) 120° D) 90° E) none of the above

C

What is the ideal angle between the H-C-H bond in methane? A) 180° B) 90° C) 109.5° D) 120° E) none of the above

C

When an alkene undergoes a hydration reaction the product is an A) aromatic. B) ether. C) alcohol. D) alkyne. E) alkane.

C

Which choice represents the carbon skeleton of 2,5-octadiene? A) C-C=C-C-C-C-C=C B) C=C=C-C-C-C-C-C C) C-C=C-C-C=C-C-C D) C=C-C-C=C-C=C-C E) C-C=C-C=C-C-C-C

C

Which of the following statements about alkyl groups is incorrect? A) -C2H5 is an example. B) 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

C

Which substance is not reactive with respect to alkanes? A) Br2 B) O2 C) H2 D) Cl2 E) none of the above

C

Alkanes and alkenes are similar in all of the following properties except A) lack of toxicity. B) solubility in non-polar solvents. C) insolubility in water. D) reactivity. E) flammability.

D

All of the families below include functional groups which contain oxygen except A) esters. B) ethers. C) ketones. D) alkyl halides. E) carboxylic acids

D

How many hydrogen atoms are contained in a molecule of 1,4-hexadiene? A) 18 B) 6 C) 14 D) 10 E) 12

D

How many structural isomers are possible for the molecular formula, C4H10? A) 2 B) 1 C) 4 D) 3 E) 5

D

In the molecule 3,3-dimethylhexane, carbon number two is A) primary. B) quaternary. C) tertiary. D) secondary. E) none of the above

D

On the basis of the number of carbon-hydrogen bonds, all of the following families of compounds can be considered unsaturated except A) alkenes. B) alkynes. C) arenes. D) alkanes. E) none of the above

D

The alkyne functional group is A) one or more bonds between carbon and nitrogen. B) 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

D

The commonly accepted mechanism for explaining alkene reactions involves formation of A) carbon atoms which have lost all their electrons. B) carbanions. C) carbon atoms with four electrons. D) carbocations. E) carbon atoms with 10 electrons.

D

The most common reactions involving aromatics are ________ reactions. A) elimination B) oxidation C) addition D) substitution E) reduction

D

What is the IUPAC name of the molecule shown? CH2=CH-CH=CH2 A) 1,4-butadiene B) 1,1-butadiene C) diethylene D) 1,3-butadiene E) 1,2-butadiene

D

What is the ideal angle between the H-C-C bond in acetylene? A) 120° B) 109.5° C) 90° D) 180° E) none of the above

D

When an alkane reacts with an element from group 7A, the reaction is referred to as A) decomposition. B) displacement. C) oxidation. D) halogenation. E) combustion

D

When an alkene undergoes hydrogenation, the product is an A) alkene. B) alkyne. C) aromatic. D) alkane. E) alcohol

D

Which factor is most important in determining the chemistry of an organic molecule? A) the number of carbon-hydrogen bonds B) the functional groups C) the number of carbon-carbon bonds D) the number of branches in the carbon chain E) the melting point

D

Which of the following reactions involves addition of two different elements to an alkene? A) bromination B) hydrogenation C) chlorination D) hydrohalogenation E) none of the above

D

Which of the statements about the behavior of the element carbon in organic molecules is incorrect? A) Carbon can be involved in polar covalent bonds. B) 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.

D

Which reactant should be used to convert propene to 2-chloropropane? A) BrCl B) Cl2 C) NaCl D) HCl E) H2

D

A substitution reaction can best be described as a reaction in which A) two reactants combine to form one new product with no extra atoms. B) a hydrocarbon reacts with oxygen to produce CO2, H2O, and energy. C) a single reactant splits into two products. D) a single reactant undergoes reorganization of its chemical bonds, producing an isomer of the reactant. E) two reactants exchange atoms to give two new products.

E

All of the following are common reactions of benzene except A) nitration. B) bromination. C) sulfonation. D) chlorination. E) hydrogenation.

E

All of the following statements are general properties of organic compounds except A) The bonds are covalent. B) 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.

E

How many hydrogens are present in a molecule composed of a six membered ring of carbon atoms and no double or triple bonds? A) 10 B) 24 C) 14 D) 16 E) 12

E

Markovnikov's Rule refers to ________ A) The rate of hydrogen addition to an alkene with alkyl group substituents. B) The temperature difference observed in the boiling points of cis and trans alkenes. C) The ideal bond angle between substituents on a double bond. D) The color of a molecule containing multiple double bonds. E) The orientation an unsymmetrical reagent will take when added to an unsymmetrical alkene.

E

The cause of cis-trans isomerism is A) strength of the double bond. B) stability of the double bond. C) vibration of the double bond. D) short length of the double bond. E) lack of rotation of the double bond.

E

The starting material for polymerization reactions is a(an) A) alkane. B) isomer. C) catalyst. D) dimer. E) monomer.

E

What is the minimum number of carbons that must be present in a molecule to have a secondary carbon? A) 1 B) 4 C) 2 D) 5 E) 3

E

When the aromatic ring is named as a side chain or functional group, it is referred to as the ________ group. A) benzoyl B) benzyl C) toluyl D) xylyl E) phenyl

E

Which choice represents the carbon skeleton of 1,6-octadiene? A) C=C-C-C=C-C=C-C B) C-C=C-C-C=C-C-C C) C=C=C-C-C-C-C-C D) C-C=C-C=C-C-C-C E) C-C=C-C-C-C-C=C

E

Which choice represents the carbon skeleton of 2,4-octadiene? A) C-C=C-C-C-C-C=C B) C-C=C-C-C=C-C-C C) C=C=C-C-C-C-C-C D) C=C-C-C=C-C=C-C E) C-C=C-C=C-C-C-C

E

Which functional group does not contain oxygen? A) ketone B) alcohol C) carboxylic acid D) ester E) amine

E

Which of the following is not the common name of an aromatic compound? A) phenol B) aniline C) xylene D) toluene E) acetone

E

Which reactant should be used to convert propene to 1,2-dichloropropane? A) BrCl B) NaCl C) HCl D) H2 E) Cl2

E