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Lecture Presentation
Chapter 12
Organic
Compounds
Bradley Sieve
Northern Kentucky University
Highland Heights, KY
© 2014 Pearson Education, Inc.
Organic Chemistry
• Organic chemistry is the branch of chemistry
dealing with carbon
• Carbon atoms can bond to themselves or to
other elements
– Form long chains or rings of many atoms
• Leads to a variety of unique physical,
chemical, and biological properties
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
• Hydrocarbon
– A compound containing only carbon and
hydrogen atoms
• Examples include CH4 and C8H18 and
polyethylene
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
• Configurations
– The way atoms are bonded to one another
• Structural Isomers
– Two molecules with the same formula but
different configurations
– Each exhibits different properties due to the
differences
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
• Conformations
– Different spatial orientations of molecules
– Atomic bonding does not change however
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Concept Check
Which carbon–carbon bond was rotated to go
from the “before” conformation of isopentane
to the “after” conformation?
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Concept Check
Bond c is the bond that rotated.
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
• Naming Hydrocarbons
– The number of carbon atoms is reflected in a
hydrocarbon’s name
– If branched, the name is based on the longest
chain of carbons
– Smaller branches are written with the prefix -yl
– Number is used to show where the branch is
attached to main chain
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
• 3-methylhexane
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
• Hydrocarbons are obtained from coal and
petroleum
– Formed from animal matter decaying in
absence of air
– Petroleum forms various hydrocarbons
through a process called fractional distillation
• Includes tar, gasoline, and natural gas
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
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Concept Check
Do the heavier or the lighter molecules
of crude oil rise to the top of the
fractionation tower?
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Concept Check
The lighter molecules found in crude oil rise
highest within the fractionation tower. These
molecules have the lower boiling points. So
the lower the boiling point is, the higher the
molecules rise.
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12.1 Hydrocarbons Contain Only Carbon
and Hydrogen
Effects of Branching in Gasoline
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12.2 Unsaturated Hydrocarbons Have
Multiple Bonds
• Carbon atoms want to form a total of four
covalent bonds
– This is a saturated hydrocarbon
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12.2 Unsaturated Hydrocarbons Have
Multiple Bonds
• Unsaturated hydrocarbons form
multiple bonds
– Either double or triple bonds between
carbon atoms
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12.2 Unsaturated Hydrocarbons Have
Multiple Bonds
• Hydrocarbon names reflect types of bonding
– Alkanes (all single bonds) end in -ane
– Alkenes (one or more double bonds) end in -ene
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12.2 Unsaturated Hydrocarbons Have
Multiple Bonds
• Double and triple bonds cannot freely rotate
– Leads to cis/trans isomerism
• Cis means the bulk of the carbons are on the
same side of the double bond
• Trans means the bulk of the carbons are on
opposite sides of the double bond
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12.2 Unsaturated Hydrocarbons Have
Multiple Bonds
• Benzene, C6H6
– An important alkene compound
– Structure has three double bonds in a flat
hexagonal ring
– Compounds containing
one or more benzene
rings are called aromatic
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12.2 Unsaturated Hydrocarbons Have
Multiple Bonds
Aromatic Compounds
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12.2 Unsaturated Hydrocarbons Have
Multiple Bonds
• Alkynes
– Triple bond containing hydrocarbons
– Acetylene, formally called ethyne, is a common
example
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12.3 Functional Groups Give Organic
Compounds Character
• Heteroatom
– An atom other than carbon and hydrogen in
organic chemistry
– Attaches to the hydrocarbon backbone of the
compound
– Has profound effects on the overall properties
of the compound
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12.3 Functional Groups Give Organic
Compounds Character
• Functional Group
– A combination of atoms that behaves as a unit
– Most are distinguished by the heteroatoms they
contain
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Concept Check
What is the significance of heteroatoms in
an organic molecule?
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Concept Check
Heteroatoms largely determine an organic
molecule’s physical and chemical properties.
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12.4 Alcohols, Phenols, and Ethers
Contain Oxygen
• Alcohols
– Organic molecules containing a hydroxyl
group (–OH)
– Small alcohols can be very polar overall
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12.4 Alcohols, Phenols, and Ethers
Contain Oxygen
• Methanol, CH3OH
– Used in production of plastics and as a solvent
– Known as wood alcohol and can be deadly if
ingested
• Ethanol, C2H5OH
– The “alcohol” in alcoholic beverages
– Produced by fermentation
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12.4 Alcohols, Phenols, and Ethers
Contain Oxygen
• Phenols
– A compound with a hydroxyl group attached
to a benzene ring
– Can act as an acid and lose the H of the
hydroxyl group
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12.4 Alcohols, Phenols, and Ethers
Contain Oxygen
• Ethers
– A compound with oxygen bound to two
separate carbon atoms
– Not readily soluble in water
– Diethyl ether was used as an anesthetic
historically
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12.5 Amines and Alkaloids Contain Nitrogen
• Amines
– Organic compounds that a nitrogen atom is
bound to one or more saturated carbon atoms
– Less soluble in water than alcohols
– Often have an offensive odor
– Found often as alkaloids, they accept H+ ions
– Normally found as tannins in nature
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12.5 Amines and Alkaloids Contain Nitrogen
Amines are weak bases
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12.5 Amines and Alkaloids Contain Nitrogen
Tannins are salts of alkaloids
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12.6 Carbonyl-Containing Compounds
• Carbonyl Group
– Contains a carbon double bond to an
oxygen atom
– Present in ketones, aldehydes, amides,
carboxylic acids, and esters
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12.6 Carbonyl-Containing Compounds
• Ketone
– A molecule where the carbonyl carbon is
bound to two other carbon atoms
– One example is acetone, which is often used
in fingernail polish remover
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12.6 Carbonyl-Containing Compounds
• Aldehyde
– When the carbonyl carbon is bound to a carbon
and a hydrogen or two hydrogen atoms
– Often are the sources of simple smells
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12.6 Carbonyl-Containing Compounds
• Amide
– Compound in which the carbonyl carbon is
bound to a nitrogen atom
– DEET, a mosquito repellent, is an example of
an amide
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12.6 Carbonyl-Containing Compounds
• Carboxylic Acid
– When the carbonyl carbon is attached to a
hydroxyl group
– The hydroxyl H atom is an acidic hydrogen,
so they are slightly acidic
– An example is acetic acid, C2H4O2, the main
ingredient in vinegar
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12.6 Carbonyl-Containing Compounds
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12.6 Carbonyl-Containing Compounds
• Ester
– An organic molecule similar to a carboxylic
acid but the H is replaced with a carbon
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12.7 An Example of Organic Synthesis
• Organic chemists mostly work to synthesis
organic compounds with practical
applications
• Often work to create large amounts of a
natural material
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12.7 An Example of Organic Synthesis
• Retrosynthesis Analysis
– Starting with simple compounds and combining
them to form the final complex compound
– Use a knowledge of easy and hard bonds to
form the desired products
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12.7 An Example of Organic Synthesis
Retrosynthesis Analysis of Multistriatin
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12.8 Organic Molecules Can Link to Form
Polymers
• Polymer
– Exceedingly long organic molecules that
contain a repeating molecular unit
• Unit is called a monomer
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12.8 Organic Molecules Can Link to Form
Polymers
Common Polymers and Their Monomers
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12.8 Organic Molecules Can Link to Form
Polymers
• Types of Polymers
– Addition polymer is formed by joining
monomer units
– Condensation polymer is formed by the loss
of a small molecule
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12.8 Organic Molecules Can Link to Form
Polymers
• Addition Polymers
– Formed by the joining of monomers without
the loss of any atoms
– Two electrons from a double bond split and
form two new covalent bonds
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12.8 Organic Molecules Can Link to Form
Polymers
• Important type of addition polymers
– Polyethylene—widespread use including milk
jugs, plastic bags, and wire insulation
– Polypropylene—tough plastic used in pipes,
suitcases, and appliances
– Polystyrene—coffee cups, packing materials,
and insulation
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12.8 Organic Molecules Can Link to Form
Polymers
PVC (polyvinyl chloride)
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Concept Check
What do all monomers that are used to make
addition polymers have in common?
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Concept Check
A multiple covalent bond between two
carbon atoms
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12.8 Organic Molecules Can Link to Form
Polymers
• Condensation Polymer
– Polymer formed accompanied by the loss of a
small molecule such as water or HCl
– Functional group from each monomer interacts
to form the leaving molecule
– One example is the formation of nylon from
adipic acid and hexamethylenediamine
molecules
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12.8 Organic Molecules Can Link to Form
Polymers
Formation of Nylon
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12.8 Organic Molecules Can Link to Form
Polymers
• Three-Dimensional Polymers
– From monomers containing three reactive
functional groups
– Contain rigid three-dimensional network
– Cannot be remelted or reshaped, so referred
to as hard-set or thermoset polymers
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12.9 A Brief History of Plastics
• Vulcanized Rubber
– Natural rubber and sulfur heated together
– The presence of sulfur resulted in disulfide
cross-linking and improved properties
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12.9 A Brief History of Plastics
• Nitrocellulose
– Originally smokeless gunpowder
– When camphor is used as the solvent, moldable
properties improve greatly and is called celluloid
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12.9 A Brief History of Plastics
• Bakelite
– Impervious to harsh acids and bases, wide
temperatures, and most solvents
– First widely used plastic
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12.9 A Brief History of Plastics
• Cellophane
– First plastic wrap
– Transparent but still protected the product
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12.9 A Brief History of Plastics
• Polymers win in World War II
– War cut off supply of rubber for the United
States, so forced to use synthetic rubber
– Used polyethylene as wire insulation for
mobile radar systems
– Other important polymers included Nylon®,
Plexiglas®, PVC, SaranTM, and Teflon®,
among many others
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Concept Check
Name at least four polymers that had a
significant impact on the effectiveness of
Allied forces in World War II.
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Concept Check
Here are six: synthetic rubber, polyethylene,
Nylon®, Plexiglas®, PVC, SaranTM, and
Teflon®
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12.9 A Brief History of Plastics
• After wartime successes, plastics were
embraced
• Over time, negative aspects have been
realized
– Inexpensive, disposable, and nonbiodegradable
– Dependence on petroleum as starting material
for formation of plastics
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