Homework Chapters 3&4
Organic Chemistry
Chem. 171
Answer the following
1. A functional group
is where chemical reactions occur in an organic molecule
determine the family name of the compound
is a specific atom or group of atoms
All of the above.
2. The functional group in alkenes is
a carbon-carbon double bond
a benzene ring
a carbon-carbon single bond
a carbon-carbon triple bond
3. The functional group in a haloalkane is
a bromine atom
a chlorine atom
a fluorine atom
Any of the above
4. The name of CH3CH2CHClCH3 is
chlorobutane
1-chlorobutane
2-chlorobutane
3-chlorobutane
2
5. Name the following compound: CH3CH=CHCH2CH3.
pentene
2-pentene
2-pentyne
2,3-pentene
6. A 6-carbon ring with a double bond is named
hexene
1-cyclohexene
cyclohexene
cyclohexane
7. The compound named 2-butyne has
a chain of four carbon atoms with a triple bond between C2 and C3
a chain of four carbon atoms with a double bond between C1 and C2
a chain of four carbon atoms with a triple bond between C1 and C2
a chain of four carbon atoms with a double bond between C2 and C3
8. Which of the following alkenes can have cis-trans isomers?
1-butene
2-butene
2-methyl-1-propene
All of the above
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9. The product of the hydrogenation of 2-butene is
2-butane
butane
2-butyne
butane
10.The addition of Br2 to cyclohexene gives
o-bromocyclohexane
bromocyclohexane
1-bromocyclohexane
1,2-dibromocyclohexane
11.The addition of HCl to 2-methyl-2-butene follows Markovnikov's Rule.
The product is
2,3-dichloro-2-methylbutane
2-chloro-2-methylbutane
3-chloro-2-methylbutane
2-chlorobutane
12.The addition of H2 to 3-methylcyclopentene gives the product named
3-methylcyclopentane
methylcyclopentane
cyclopentene
cyclopentane
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13.The name of the isomer of 2-butene with the methyl groups on opposite
sides of the double bond is
2-butene
cis-2-butene
trans-2-butene
2,2-dimethylethylene
14.The addition of Cl2 to 4-methyl-2-pentene gives the product named
2,3-dichloro-2-methylpentane
None of the above
3, 4-dichloro-2-methylpentane
2, 3- dichloro-4-methylpentane
15.Polyethylene is a compound
known as a polymer
made of repeating units called monomers
made from many molecules of ethene
all of the above.
16.The structural isomer shown is for which one of the following
compounds?
1.
2.
3.
4.
Pent-1-ene.
Pent-2-ene.
Pent-1-yne.
Pentane.
17. Which one of the following compounds is a saturated hydrocarbon?
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1.
2.
3.
4.
Ethyne
Propene
Cyclohexene
Cyclohexane
18. The general name for the group of compounds that contain carbon and hydrogen only
is
1.
2.
3.
4.
alkynes.
hydrocarbons.
alcohols.
carbohydrates.
5. 19. Which hydrocarbon is represented by the structure shown?
1.
2.
3.
4.
Cyclohexane
Cyclohexene
Benzene
Methylbenzene
20. What is observed when ethene is reacted with acidified potasssium permanganate
solution?
1.
2.
3.
4.
The permanganate burns with a smoky flame.
Nothing happens.
The gas, carbon dioxide is formed.
The purple colour of the permanganate disappears.
21. What is the correct IUPAC name for this alkyl group
1.
2.
3.
4.
pentyl group
propyl group
butyl group
ethyl group
22. Which one of the following statements is INCORRECT?
1.
2.
The old name for the alkanes was the paraffins
Alkanes are much more stable than alkenes because of the presence of the C=C double
bond.
3. Alkynes may have one or more triple bonds in their structure.
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23. Select the simplest hydrocarbon from the following list.
1.
2.
3.
4.
Ethene.
Ethane.
1-methylpropane
Methane.
24. Show how you could make 2-bromobutane starting from an alkene.
25.Draw the structure of 6-bromo-2-chloro-4-octyne
26.Write the chemical equation for the preparation of the following compounds
1- 1-hexayne from acetylene.
2- 5-methyl 2-hexayne from 1- hexayne
3- 1-decayne from 1,2 dibromodecane
27-Complete the following equations
12-
CH3
C
C
HCl
CH3
Cl2
CH3
C
C
CH3
CH3
C
C
CH3
H2O
H2SO4
3CH3
C
CH3
C
C
CH3
4-
56-
C
CH3
Li
Lindlar,s Catalyst
Li ,
Lindlar,s Catalyst
Mechanism of addition of HBr to an alkyne
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28.Discuss(by chemical equation )
1- Addition of Br2 to 1- propene.& 1-cyclohexene (Addition of halogen to the
alkene).
2- Ozonolysis of 2- Hexene.
3- Effect of Sulfuric acid on alkene (with Example).
4- Addition of water (Hydration ) of alkene.
5-Alkylation of alkene.
6-Preparation of ( Ethylene & 1- butane).
29.Alkanes, alkenes, and alkynes are the three main families of aliphatic hydrocarbons.
(a) What is the general molecular formula for each family?
(b) What is the main structural feature of each family?
(c) Why does the number of hydrogen atoms in the molecular formula decrease by two
as you go from alkanes to alkenes, and then to alkynes?
30. Explain what is meant by the term “unsaturated” as applied to a hydrocarbon.
31. Draw a line formula and a structural formula for each of the following hydrocarbons:
(a) 3-ethyl-4-methylpent-2-ene
(b) 5-ethyl-2,2,6-trimethylhept-3-yne
32.Write the structure of the major organic product formed in the reaction of 1-pentene with
each of the following:
(a) Hydrogen chloride
(e) Conc. sulfuric acid
(h) Bromine
(j) Ozone
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33.Outline efficient syntheses of each of the following alkynes from acetylene and any
necessary organic or inorganic reagents:
(a) 1-Heptyne
(b) 2-Heptyne
(c) 3-Heptyne
34.Write a series of equations showing how you could prepare 1,1-dichloroethane from
(a) Ethylene
(b) Vinyl chloride (CH2=CHCl)
(c) 1,1-Dibromoethane
35.Give the structure of the enol formed by hydration of 2-butyne,and write equations showing
its conversion to its corresponding ketone isomer.
36.Write a structural formula or build a molecular model of each of the following:
(a) 1-Octyne
(b) 2-Octyne
(c) 3-Octyne
(d) 4-Octyne
(e) 2,5-Dimethyl-3-hexyne
(f ) 4-Ethyl-1-hexyne
(g) Ethynylcyclohexane
(h) 3-Ethyl-3-methyl-1-pentyne
All the compounds are isomers except one. Which one?
37.Identify the alkene obtained on dehydration of each of the following alcohols:
(a) 3-Ethyl-3-pentanol
(b) 2-Propanol
(c) 1-Propanol (
d) 2,3,3-Trimethyl-2-butanol
38.Arrange the following alkenes in order of decreasing stability:
1-pentene; (E)-2-pentene; (Z)-2-pentene; 2-methyl-2-butene.
39.Classify each of the following as an internal or a terminal alkyne:
(a) 1-hexyne
(b) cyclooctyne
40.What would the products of the
ozonolysis reactions of:
(a) ethyne ?
(b) 1-butyne ?
(c) 3-octyne
(d) propyne
c) 2-butyne ?
(d) cyclooctyne ?
41.What would be the product from the reaction of 2-butyne with excess HBr ?
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42.What is the prefix for naming hydrocarbons and What is the suffix for naming
hydrocarbons?
43.Are hydrocarbons polar or non-polar?
44.Mention three different types of addition reactions?
45.When 1-hexyne was treated with aqueous sulfuric acid containing mercury(II) sulfate, two
products, were obtained . What are these two compounds?
Choose the correct answer (major product)
1)
Br
H
is:
A) (Z)-3-Bromo-4-methyl-2-hexene.
B) (Z) -4-Bromo-3-methyl-4-hexene.
C) (E)-3-Bromo-4-methyl-2-hexene
D) (E) -3-Bromo-4-ethyl-2-pentene.
_____________________________________________________________________
2)
OH
is:
A) 2,3-Dimethyl-1-hexen-5-ol.
C) 4-Propenyl-2-pentanol.
B) 4,5-Dimethyl-5-hexen-2-ol.
D) 5-Hydroxy-2,3-dimethyl-1-hexene.
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_____________________________________________________________________
3)
Br
is:
O
A) 3-Bromo-3-ethoxy-1-propene.
B) 3-Bromo-3-methoxy-1-propene.
C) 4-Bromo-5-hexene.
D) 1-Bromo-1-ethoxy-2-propene.
4)
Cl
is:
A) 4-Chloro-2-hexen-5-yne.
B) 3-Chloro-4-hexen-1-yne.
C) 2-Chloro-4-penten-1-yne.
D) 3-Chloro-1-hexyn-4-ene.
5) Which of the following is structural isomer of 3-hexyne?
A)
B)
C)
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D)
6)
H3C
C
C
CH3 +
Na / liq. NH3
H2
A) n. Butane.
B) Cis-2-butene.
C) 1-Butyne.
D) Trans-2-butene.
7)
O
Br
NH 2 is:
A) 2-Amino-3-bromo-5-hexanone.
C) 4-Acetyl-2-amino-3-bromobutane.
B) 3-Bromo-5-hexanon-2-amine.
D) 5-Amino-4-bromo-2-hexanone.
8) 6-Bromo-2-ethyl-3-hydroxyhexanal is:
Br
OH
Br
CHO
A)
B)
CHO
CH 3
OH
OH
C)
OH
D)
CHO
Br
Br
O
_____________________________________________________________________
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9) 2-Cyclohexene carboxylic acid is:
COOH
COOH
A)
B)
CHO
D)
C)
COOH
_____________________________________________________________________
10)
HO
Br
is:
(A) 4-Bromo-3-ethyl-1-hydroxycyclohexane.
(C) 1-Bromo-2-ethyl-4-cyclohexanol.
(B) 3-Ethyl-4-bromocyclohexanol.
(D) 4-Bromo-3-ethylcyclohexanol.
_____________________________________________________________________
11) 3-Cyclopentene aldehyde is
CHO
a)
COOH
COOH
CHO
b)
c)
d)
12)What is the best name for the following compound?
H
H
C
CH3-CH2
CH2-CH2CH3
C
a) 3-Methylenehexane
b) 2-Propyl-1-butene
c) 4-Ethyl-4-pentene
d) 2-Ethyl-1-pentene
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13)The correct IUPAC name of the following compound is
O
H
a) 3-Methyl-5-Hexenal
b) 1-Heptenal
c) 4-Methyl-5-hexenal
d) 4-Methyl-5-hexyneal
14)Identify this hydrocarbon:
1-butane
2-propane
3-pentane
15)Identify this hydrocarbon:
hexene
heptene
septen
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16)Identify this hydrocarbon:
hexyne
butyne
propyne
17)Identify this hydrocarbon:
propane
ethene
propyne
ethane
18)This molecule is an example of an:
alkane
alkene
alkyne
none of the above
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19)This molecule is an example of an:
alkane
alkene
alkyne
20)What is the molecular formula for this hydrocarbon?
C 5 H6
C 5 H9
C5H10
21)What is the molecular formula for this hydrocarbon?
C4H4
C3H6
C4H6
C3H8
C4H10
C5H12
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22)Identify this hydrocarbon:
1-hexene
2-hexene
3-hexene
4-hexene
5-hexene
23) Which of the following can exist as cis-trans isomers?
(a) CH2=CHCH2CH2CH3
(b) CH3CH2CH=C(CH3)CH2CH3
(c) CH3CH2CH=CHCH2CH3
(d) CH3CH2CH=CBr2
24) Write the formulas for the following named compounds:
(a) trans-2-Heptene
(b) Z-2-Bromo-1-chloropropene
(c) Vinylcyclopropane
(d) Allylcyclopentane
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