Download Chapter 12: Alkanes

Chapter 12: Alkanes
Chapter Objectives (aka...What is going to be on the exam)
1.!
!
What are the basic properties of organic compounds? Be able to identify
organic compounds and the types of bonds contained in them.!
2.!
!
!
What are functional groups, and how are they used to classify organic
molecules? Be able to classify organic molecules into families by functional
group.
3.!
What are isomers? Be able to recognize and draw constitutional isomers.
4.!
!
How are organic molecules drawn? Be able to convert between structural
formulas and condensed or line structures.
5.!
!
!
What are alkanes and cycloalkanes, and how are they named? Be able to
name an alkane or cycloalkane from its structure, or write the structure, given the
name
6.!
!
!
What are the general properties and chemical reactions of alkanes? Be
able to describe the physical properties of alkanes and the products formed in
the combustion and halogenation reactions of alkanes.
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Chapter 12: Alkanes
1. What are the basic properties of organic compounds? Organic chemistry is the branch of chemistry that deals with the study of carbon based
compounds.
Organic molecules have covalent bonds.
Organic molecules contain polar covalent bonds when carbon bonds to an
electronegative element on the right side of the periodic table.
There are over 18 million known, and many more unknown possible structures ranging
from one C to over a million carbons, and containing other elements such as N, O, S.
!
!
!
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Chapter 12: Alkanes
Carbon Review
Carbon has 4 valence electrons and can form 4 bonds. Covalent molecules can form
polar covalent or non polar covalent bonds.
Hydrocarbons:
12.48
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Chapter 12: Alkanes
2.! What are functional groups, and how are they used to classify
organic molecules?
Functional group:
12.27, 12.32 b, 12.33
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Chapter 12: Alkanes
3.!
What are isomers?
Isomers:
Constitutional Isomers:
Different constitutional isomers are completely different chemical compounds with
different structures, different physical properties and potentially different physiological
properties.
12.36, 12.46
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Chapter 12: Alkanes
4. How are organic molecules drawn?
Condensed structure:
Bond-line structure (skeletal structure):
Conformers:
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Chapter 12: Alkanes
5. ! What are alkanes and cycloalkanes, and how are they named?
Alkane:
Straight-chain alkane:
Branched-chain alkane:
12.19, 12.21
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Chapter 12: Alkanes
Composed of a prefix that tells how many carbons there are
Composed of a suffix that tells whether that the molecule is an alkane
-ane
Alkyl Group:
!
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Chapter 12: Alkanes
Naming Branched Alkanes, Alkenes and Alky
Branched Alkanes
1.
Name the longest chain.
2.
Number that chain so as to give the lowest number priority to any branched groups.
3.
Name the branched groups.
4.
Write the full name as one word:
a.
Use hyphens to separate numbers from prefixes
b.
Use commas to separate numbers from other numbers
c.
Use alphabetical order to list branched groups
Branched Alkenes and Alkynes
1.
Name the longest continuous chain containing the double or triple bond.
2.
Number the chain giving the lowest priority to the double or triple bond.
3.
Write the full name as one word:
a.
Use hyphens to separate numbers from prefixes
b.
Use commas to separate numbers from other numbers
c.
Use alphabetical order to list branched groups
d.
If it is an alkene, do cis-trans isomers apply?
12.38, 12.23, 12.50, 12.52
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Hydrocarbons
ChapterCyclic
12: Alkanes
Cycloalkanes
yclic Alkanes
H2C
H2C
CH2
H2C
H2C
CH2
H2C
cyclobutane
H2
C
H2
C
CH2
H2C
CH2
cyclopropane
H2C
CH2
H2C
CH2
C
H2
cyclohexane
H2C
C
H2
C
H2
cyclopentane
H2C
CH2
CH2
H2C
H2
C
CH2
CH2
H2C
CH2
H2C
CH2
C
H2
cycloheptane
C
H2
cyclooctane
Cycloalkanes
1. Use
cycloalkane name as the parent.
Cyclic Alkenes
andthe
Alkynes
H2C
HC
CH2
H C
CH2
C
C
2
HC
2. ! Identify
and number the substituents.
H C
cyclopropene
CH2
2
CH2
cyclooctyne
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Chapter 12: Alkanes
6.! What are the general properties and chemical reactions of
alkanes?
1.
2.
3.
4.
5.
Reactions of Alkanes:
Combustion:
Halogenation:
12.70, 12.60, 12.62
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Chapter 12: Alkanes
Sample Problems
1.
Draw and name the unbranched alkane with 5 carbons.
2.
Draw and name all 5 isomers of hexane
Sample Problems
Circle and name each functional group:
3. ! Circle and name each functional group
Draw:
butane
O
propene
2-butene
O
2-methyldecane
cyclopentane
O
methylcyclohexane
3-methylcycloheptene
HO
Name:
OH
H
O
H
H
H2N
O
acetylsalicylic acid; aspirin
testosterone; a steroid/sex hormone
OH
phenylalanine; an essential amino acid
CH4
4.
Problems:
Name:
1)
Draw and name the saturated, unbranched alkane with 5 carbons.
2)
Draw all 5 isomers of hexane.
3) Draw 2-methyl-2-butene. Why is there no cis-trans isomers?
Why do we not specify the location of the double bond in propene?
Why is there no such compound known as methyne?
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