Download Chapter 2 Atoms and Elements

Chapter 8 Chemical
Reactions of Inorganic and
Organic Compounds
8.4
Functional Groups in Organic
Compounds
Elements in Organic
Compounds
In organic molecules, carbon (C) atoms
• form bonds with H and other C atoms
• can also form bonds with atoms of O, N, S and
halogens F, Cl, and Br
Esters such as ethylbutanoate
provide the odor and flavor of
many fruits such as pineapples.
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Functional groups are
• a characteristic feature of organic molecules
that behave in a predictable way
• composed of an atom or group of atoms
• replace H on a carbon chain
• a way to classify families of organic
compounds
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Alkenes, Alkynes, and Aromatic
Compounds
Functional Groups
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Example of an Alkene
• Alkenes contain a double
bond between adjacent
carbon atoms.
• Alkynes contain a triple
bond between adjacent
carbon atoms.
• Aromatic compounds
contain a benzene ring of six
carbon atoms.
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Alcohols and Ethers
• An alcohol contains the
hydroxyl (-OH) functional
group.
Ethene, an alkene,
• contains a double bond
• is a plant hormone,
which promotes the
ripening of fruit
• In an ether, an oxygen
atom is bonded to two
carbon atoms.
Fruit is picked early and
ripened by exposure to ethane.
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Aldehydes and Ketones
• An aldehyde contains a carbonyl
group (C=O), a carbon atom with a
double bond to an oxygen atom,
which is attached to at least one
hydrogen.
• In a ketone, the carbon of the
carbonyl group is attached to two
other carbon atoms.
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Carboxylic Acids and Esters
• Carboxylic acids
contain the carboxyl
group, which is a
carbonyl group attached
to a hydroxyl group.
• An ester contains the
carboxyl group
between carbon atoms.
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Example of a Ketone
Propanone (acetone), a
ketone,
• is the simplest ketone
• contains a carbon-oxygen
double bond
• is used as a solvent for
paint and nail polish
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Basic Chemistry
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Examples of a Carboxylic Acid
and an Ester
Ethanoic acid, or
acetic acid,
contains a carboxyl
group.
In methyl acetate, an
ester, the O atom
of the carboxyl
group is attached
to a carbon.
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Amines and Amides
• In amines, the functional
group is a nitrogen atom.
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Examples of Amines
Amines are found
• in the body and in drugs
• In amides, the hydroxyl group
of a carboxylic acid is replaced
by a nitrogen group.
• in amino acids
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Examples of Amides
Classification of Organic
Compounds
Amides are found
• in sweeteners
• in peptide bonds between
amino acids in proteins
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Basic Chemistry
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Learning Check
Classify each of the following as alcohol, ether,
aldehyde, ketone, carboxylic acid, ester, amide, or
amine:
1. CH3─CH2─CH2─OH
2.
CH3─O─CH2─CH3
3.
CH3─CH2─NH2
O
║
4. CH3─C─OH
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Basic Chemistry
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Chapter 8 Chemical
Reactions of Inorganic and
Organic Compounds
8.5 Reactions of Organic
Compounds
O
║
5. CH3─C─O─CH3
A mixture of acetylene and oxygen undergoes
combustion during the welding of metals.
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Combustion
Combustion of Propane
In a combustion reaction,
In a combustion reaction,
• an organic compound reacts with oxygen, O2
• propane reacts with oxygen, O2,
• the products are CO2, H2O, and energy
C3H8(g) + 5O2(g)
• for methane, the balanced equation is
CH4(g) + 2O2(g)
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

3CO2(g) + 4H2O(g) + heat
CO2 (g) + 2H2O(g) + heat
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Learning Check
Combustion of Alcohols
Balance the combustion equation for pentane.
__C5H12 + __O2

An alcohol such as ethanol undergoes combustion.
__ CO2 + __H2O + heat
CH3─CH2─OH + 3O2

2CO2 + 3H2O + heat
A dessert is heated by a combustion reaction.
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Hydrogenation
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Products of Hydrogenation
In a reaction called hydrogenation,
Adding H2 to vegetable oils produces
• a hydrogen atom adds to each carbon atom of
a double or triple bond
• compounds with higher melting points
• a catalyst such as platinum is used
• margarines
• soft margarines
• shortenings (solid)
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Learning Check
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Concept Map
Write an equation for the hydrogenation of
CH2 = CH─CH2─CH3 using a platinum
catalyst.
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