Activity #2
Name :_______________
The Hydrocarbons and Their Derivatives:
Nomenclature, Physical/Chemical Properties, and Synthesis.
Background
Hydrocarbons are compounds containing only carbon and hydrogen. Hydrocarbons are
usually divided into different types, depending on the actual functional group. For
example, saturated hydrocarbons include the alkanes, unsaturated hydrocarbons
include the alkenes and alkynes, while aromatic hydrocarbons include benzene and its
many derivatives. Substituting any alkyl group (methyl, ethyl, etc.) for one or more
hydrogen atoms within these families does not affect their “hydrocarbon” status,
through you have produced an alkyl derivative of these families. But substituting a
halogen (F, Cl, Br, I) for one or more hydrogen atoms within these families results in a
“halo derivative” being formed which, by inspection, is no longer just a hydrocarbon.
The general formula for an alkane is CnH2n +2, while the general formula for an alkene is
CnH2n, while that for an alkyne is CnH2n-2.
Objectives
To practice writing names and formulas for the hydrocarbons and their derivatives
To experience some chemical tests that will differentiate between the different types of
hydrocarbons
To practice completing reactions for the hydrocarbons
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Directions
Part 1. Nomenclature of the Hydrocarbons and Their Derivatives
Give names or structures for the following:
1. CH 3CH3
9.
CH3CHBrCH2CH2Br
2.
CH3CH2CHCH3
Br
10.
CH3CH=CHCH2CH
3.
BrCH2CH2CH2Br
11.
CH3CCCH2CH3
12.
Benzene
13.
Methylbenzene
4.
5.
1-Chlorocyclohexene
1, 3- dimethyl 1-cyclopentene
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6.
CH2C(CH3)2
14.
CH3CH2CH2CHCH2CH2CH3
CH3
7.
Aminobenzene
15.
CH3CH2CHCHCH2CH3
8.
Br CH3
CH3-CH-CH-C-CH3
Br
CH3
16.
ethylbenzene
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Give a structure for the following names:
1. propane
8. 2,2-dichloropentane
2. octane
9. 4-ethyl-2-methylhexane
3. 3-ethyloctane
10. 2,3-dimethyl-2-butene
4. trans-1,2-difluoropropene
11. cis-2-pentene
5. 3-hexyne
12. 2-bromo-propane
6. chlorobenzene
13. cyclobutane
7. benzoic acid
14. ethyl benzene
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The following names are incorrect. State why they are incorrect and then give their
correct names.
1-chloroethane:
3-bromobutane:
2-chloro-3-bromo-4-methylhexane
trans-1-propene
1-bromo-3-pentyne
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Part 2. Chemical Tests Used to Differentiate Between the Hydrocarbons. A
Demonstration.
As your instructor demonstrates these reactions, respond to the following questions.
Combustion
What type of flame is produced when an alkane is burned?
What type of flame is produced when an alkene is burned?
What type of flame is produced when an alkyne is burned?
What type of flame is produced when an aromatic compound is burned?
Halogenation: Iodination.
What color results when iodine is added to an alkane?
What color results when iodine is added to an alkene?
What color results when iodine is added to an alkyne?
What color results when iodine is added to an aromatic compound?
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Halogenation. Bromination.
Record what happens when a solution of bromine in acetic acid is added to hexane:
Record what happens when a solution of bromine in acetic acid is added to hexene:
Record what happens when a solution of bromine in acetic acid is added to hexyne:
Record what happens when a solution of bromine in acetic acid is added to toluene:
Based on these two chemical tests, state how can you chemically differentiate between
a) a saturated hydrocarbon and an unsaturated hydrocarbon?
b) a saturated hydrocarbon and an aromatic hydrocarbon?
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c) an unsaturated hydrocarbon and an aromatic hydrocarbon?
Part III. Reactions of Hydrocarbons
Complete the following reactions:
1.
Cl2
CH3CH3------------------_________________________
light
2.
-------------------- ___________________________
Br2, light
3.
CH2=CH2 + H2O----------------------
4.
HCCCH2CH3 ---------------------
Excess H2, Pt
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