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Chapter 12
Organic Chemistry
12-1
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Chapter 12 Outline: Main Ideas

Carbon compounds
◦ Bonds and types
◦ Petroleum products

Organic molecule structures
◦ Formulas and structure

Organic compounds
◦ Groups
◦ Polymers

The chemistry of life
◦ Molecules important for biological
processes
12-2
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Carbon Compounds
ORGANIC
CHEMISTRY
THE STUDY OF
CARBON-CONTAINING COMPOUNDS
12-3
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Why Is Organic Important?
ORGANIC CHEMISTRY constitutes a separate
branch of chemistry
 We are made of carbon….
 Over 90% of all compounds contain the
element CARBON
 There are over 3 MILLION known organic
compounds
◦ Over 100,000 are added EACH YEAR

CONTRAST: only about 300,000 Inorganic
compounds
12-4
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ORGANIC COMPOUNDS
CONTAIN CARBON
Know the Difference!
DO NOT contain
carbonINORGANIC
COMPOUNDS
12-5
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Interesting Organic Trivia

Until around 1850, scientists believed
that organic compounds could only be
formed by LIVING THINGS….
◦ They even considered organic compounds
to have some “VITAL FORCE” associated
with LIFE
◦ Then, Friedrich Wohler successfully
formed a SYNTHESIS reaction…
Ammonium
cyonate
UREA
The primary ingredient in urine
12-6
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Organic Chemistry Is Born
After Wohler’s demonstration…MANY
“natural” organic molecules were
produced by chemists
 Then, organic molecules that DO NOT
OCCUR naturally were produced at an
ever increasing pace

12-7
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Organic Chemistry Is Important
Organic chemicals are being introduced
into the environment at an astonishing
rate
 Organic chemistry has IMPLICATIONS
to a wide variety of fields of study:

◦ MEDICINE
◦ BIOLOGICAL SCIENCES
 Agriculture
 Civil engineering
 Water management
12-8
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Why Is Carbon so Unique?
The carbon atom can form bonds with
MANY other elements
 The carbon atom forms a VARIETY of
different bonding structures
 We have already seen that the covalent
bonds between carbon atoms can result
in vastly different structures

◦ Graphite, diamond
12-9
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Carbon Is Unique

The position of the Carbon atom on the
periodic table is a clue to its versatility
◦ Carbon is located midway in its period
◦ This means that the outer electron shell is
HALF FULL
 Instead of gaining or losing electrons, carbon has
the natural tendency to SHARE electrons in order
to complete its outer shell

The unique bonding ability of carbon
extends to bonds with other elements
as well
12-10
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The Simplest Organic Molecules

Those that contain only CARBON and
HYDROGEN
Very simple structures
Very important variety
We depend STRONGLY on the chemistry of the
hydrocarbons
12-11
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The Alkane Group

This group of hydrocarbons includes
many familiar gases used in everyday
life
12-12
Some Members of the Alkane
Group
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Methane……………CH4
 Ethane……………….C2H6
 Propane………………C3H8
 n-Butane………………C4H10
 n-Pentane………..……..C5H12
 n-Octane………………….C8H18
 Note: the natural gas used for household
purposes consists of several alkanes

◦ Primarily methane, about 80%
12-13
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Petroleum Products
 Crude oil is the basic raw ingredient for
the production of useful petroleum
based fuels
 This natural resource is a combination
of several alkanes
◦ Those with 5+ carbon atoms
◦ The exact proportion of each alkane
depends on the source of the crude oil
12-14
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Distillation
 In order to effectively use crude oil,
some alkanes must be at least
partially separated from the rest
◦ This is a difficult process, since the
physical and chemical properties of the
members of the alkane family are very
similar
 The solution to this problem is
found in the process of
FRACTIONAL DISTILLATION
12-15
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Using Hydrocarbon Fuels
FRACTIONAL DISTILLATION
REFERS TO THE PRODUCTION OF
SEVERAL HYDROCARBON
COMPOUNDS
 Made possible by thoroughly
understanding the detailed properties
and small differences between each of
the compounds present in crude oil

12-16
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Fractional Distillation: Basic Idea
 The crude oil is heated
 At each increasing temperature,
some alkanes will evaporate,
◦ Vapors are collected and further
refined to separate the multiple
compounds that may be present in
the vapor
 This requires a specially
engineered tower
12-17
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More about Fractional Distillation

The natural resource: Crude oil
◦ Complicated mixture of hydrocarbons;
composition varies depending on its source

Each hydrocarbon in crude oil has a different
boiling point
◦ Varies according to the number of carbon atoms
their molecules contain and how they are
arranged

Fractional distillation uses the difference in
boiling points and vaporization points to
separate the hydrocarbons present in crude
oil
12-18
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Figure 12-2
The
Distillation
Tower
Several
steps
are
required
to
produce
fuels
12-19
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Engineering the Tower

THE FRACTIONING COLUMN
◦ A TUBE, that is cooler at the top than the
bottom
◦ The boiling vapors cool as they rise
◦ Vapors condense onto a tray when they
reach the part of the column which is
cooler than their boiling point
12-20
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Reactions Involved in FD

Catalytic “cracking”
◦ Large hydrocarbon molecules decomposed
into smaller molecules via the introduction
of a catalyst
 Requires PRESSURE
 Requires CATALYST ASSISTANCE

POLYMERIZATION
◦ Small light hydrocarbons, synthesized into
larger molecules
12-21
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More on Catalytic Cracking
“Cracking” is the name given to
breaking up large hydrocarbon
molecules into smaller and more useful
bits
 Can be achieved in two ways:

◦ By using high pressures and temperatures
without a catalyst
◦ Lower temperatures and pressures in the
presence of a catalyst.
12-22
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Useful Catalysts


The catalyst is not unique
One common catalyst is small zeolite
crystals
◦ Zeolite = aluminosilicate mineral

The catalyst/hydrocarbon mixture is then
blown reaction chamber at a temperature
of about 500°C.
◦ This is called fluid catalytic cracking

The catalyst (solid) remains in a different
phase than the liquids to be separated
12-23
Organic Molecule Names
The name simply lists the numbers of each
element present in the compound
 The name does not yield any information
regarding the actual structure of the molecule
◦ Bonding
◦ Arrangement
 For example, butane is C4H10

12-24
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A Word on Structural Formulas

A structural formula is a diagrammatic
way to illustrate the actual arrangement
of the atoms in an organic molecule
◦ The arrangement yields information on
how the molecule will interact with other
molecules, depicting how the atoms are
bonded to each other

One useful means of illustrating
molecular structure is by using the
displayed formula
12-25
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The Displayed Formula
A displayed formula shows all the bonds in
the molecule as individual lines. You need
to remember that each line represents a
pair of shared electrons.
 Methane (CH4) displayed formula

H
H
C
H
H
12-26
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The Displayed Formula

The benefit of the displayed formula is
that it gives more information about the
structure of the molecule.
◦ Instead of knowing only how many of each atom,
the structural formal tells us which atoms are
bonded to which other atoms

There is a limitation to the information:
the way the methane is drawn bears no
resemblance to the actual shape of the
molecule.
◦ Methane is not “flat” with 90° bond angles
12-27
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Arrangement Is Important
Some organic chemicals share the same
molecular formula, but have different
properties
 An ISOMER is a different arrangement
of the same atoms for a particular
organic species
 EXAMPLE butane

12-28
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The Butane Isomer
Butane has the molecular formula: C4H10
 The same atoms can be arranged in two different
structures

NORMAL
H H BUTANE
H H
H
C
H
C
H
C
H
C
H
H
H
H
C
C
C
H
C
H
H
H
H
H
H
ISOBUTANE
12-29
H
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More about Carbon Bonding

The alkane group contains the simplest
hydrocarbon molecules
◦ Only carbon and hydrogen atoms
◦ Only single covalent bonds between any two atoms
There are other hydrocarbons, also
containing only hydrogen and carbon that
exhibit more complex bonding structures
 Due to the unique properties of carbon
atoms:

◦ Two carbon atoms can form DOUBLE and TRIPLE
COVALENT BONDS
12-30
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Example
Consider the molecular formula C2H6
 This is the alkane ETHANE:

H
H
H
C
C
H
Note that the
only difference
H H
is in the bond
 This is also a non-alkane hydrocarbon,
between the
two center
ETHYLENE:
H H
carbon atoms!
H
C
C
H
H
H
12-31
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Multiple Bonds Affect the Activity


The alkanes, with only single bonds, are
the least reactive
Those molecules with double or triple
bonds are more chemically reactive
◦ The presence of a multiple bond means that
the molecule has “room” to add another atom
◦ They are thus called UNSATURATED

The alkanes are called SATURATED, since
other atoms cannot be added to the basic
structure
12-32
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Other Atomic Arrangements
Not all organic molecules are arranged
in a linear fashion like the ones we have
seen
 A special class of organic molecules,
called AROMATIC COMPOUNDS contain
a ring of carbon atoms
 This 6-member carbon ring is called
BENZENE

12-33
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The Benzene Ring

The BENZENE RING is hexagonal in
shape
◦ The bonds between the carbon atoms in the
ring are not simple single bonds.
◦ In addition to the ordinary single bond, an
additional 6 electrons are shared by the
carbon atoms
H
H
C
C
H C
C H
C
H
C
12-34
H
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Aromatic Compounds
 The name aromatic was given to
this class of carbon compounds
due to the strong odor of many of
the compounds
◦ Benzene
◦ Toluene
◦ Napthalene
12-35
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Two Main Classes

Organic compounds that contain the
ring structures:
AROMATIC

Organic compounds that do not contain
ring structures:
ALIPHATIC
12-36
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Classification of Organic Chemicals


Compounds that contain elements other
than hydrogen or carbon are considered to
be DERIVATIVES of the more fundamental
carbon-hydrogen combinations that we
have considered thus far.
The basic idea is to substitute an atom or
group of atoms at the location of one of the
hydrogen atoms linked to the carbon
chain that forms the central structure in
the organic molecule
12-37
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The Simplest Substitutions

The most simple groupings are derived
from the hydrocarbons themselves
◦ The Methyl group 1 C, 3H
◦ The Ethyl group, 2 C, 5 H
◦ The Propyl group, 3 C, 7H

These abbreviations are used in naming
more complex compounds
◦ For example, Methyl Chloride, CH3Cl
12-38
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Functional Groups

Certain sets of atom groups exhibit
similar properties
◦ We saw this in our look at inorganic
chemicals, in particular in acids and bases

In organic compounds, these similaracting groups are known as
FUNCTIONAL GROUPS
◦ See Table 12-2 in the text: this table lists a
variety of common functional groups
12-39
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Organic Compound Behavior
The chemical behavior of organic
compounds is largely determined
according to which functional groups
are present
 Each functional group is responsible for
some characteristic of a group of
organic compounds
 These groups include alcohols, ethers,
aldehydes, ketones and organic acids

12-40
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The Alcohol Group
All alcohols contain an OH- group, called the
HYDROXYL GROUP

This is shown in a name by the ending
“ol”
The word alcohol derives from Arabic alkuhul, which denotes a fine powder of
antimony obtained by distillation
 Alcohol originally referred to any fine
powder, but medieval alchemists later applied
the term to the refined products of distillation

12-41
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Beverage Alcohol

Ethanol
◦ Chemical formula: CH3CH2OH

Physical Properties
◦ Ethanol melts (or freezes) at about –114.1 °C
(about -173 °F)

Its low freezing point has made it useful as
◦ The fluid in thermometers for
temperatures below –40 °C, the
freezing point of mercury
◦ Use as antifreeze in automobile
radiators.
12-42
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Ethanol

Has been made since ancient times by the
fermentation of sugars



All beverage ethanol and more than half of
industrial ethanol is still made by this
process.
Simple sugars are the raw material.
Zymase, an enzyme from yeast, changes
the simple sugars into ethanol and carbon
dioxide.
12-43
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Fermentation

The fermentation reaction, is
represented by the simple equation
C6H12O6  2CH3CH2OH + 2CO2
The equation is simple, but the
fermentation process is actually very
complex
 IMPURITIES IN SOLUTION:

◦ In the production of beverages, such as
whiskey and brandy, the impurities supply
the characteristic flavor.
12-44
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Ethers, Aldehydes and Ketones

ETHERS
◦ Substances that has an oxygen atom bonded
between two carbon atoms
◦ Widely used as a solvent

ALDEHYDES and KETONES
◦ Both groups contain the CARBONYL ATOM
GROUP:
C
O
12-45
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The Carbonyl Group




The double bond between the carbon
atom and the oxygen atom on the end of
the group cause strong polarity of this
group
This means that aldehydes and ketones
are readily soluble in water
Most common ketone: acetone
Familiar aldehyde: acetaldehyde
◦ This is a product produced by the oxidation of
ethanol and becomes further oxidized to form a
toxic substance, formaldehyde
12-46
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Organic Acids

This group of organic compounds
contain the COOH or CARBOXYL group
◦ Organic acids have most of the same
properties as ordinary acids, resulting from
the liberation of the H+ ion from the
Carboxyl group

Organic acids in everyday experience:
◦ Insect bites: formic acid
◦ Vinegar: acetic acid
◦ Aspirin: acetylsalicylic acid
12-47
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Esters

When an alcohol reacts with an acid, the
reaction is quite slow when compared
with ordinary inorganic acid-base
reactions
◦ This is due to the slow dissociation of the
hydroxide in the alcohol in water

The reaction of the “organic hydroxide”—
the alcohol with the organic acid is very
slow, with the product being a separate
group of organic compounds called
ESTERS
12-48
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Esters


Like ketones, esters are also used as
solvents
Esters in everyday life:
◦ Ethyl acetate: used in paint
◦ Propyl acetate: causes the characteristic
fragrance and taste of pears
◦ Butyl butyrate: responsible for the
characteristic fragrance and taste of pineapple
◦ Nitroglycerin: an explosive liquid that was once
the main stay of demolition work
12-49
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Linking Basic Groups Together
 When multiple small organic
molecules are linked together, a
long, chain-like molecule is formed
 These very large molecules are
called
POLYMERS
 Much of modern life revolves
around the use of polymers
12-50
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Polymers

All man-made plastic materials are
polymers:
 Polythene (packing material)
 Polyvinylchloride (used for pipes)
 Teflon, nylon, dacron, polyester and styrofoam

In addition, many natural substances
are polymers:
 Starches
 Cellulose (wood fiber)
 Proteins
12-51
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Polymer Formation
Polymers are formed when MONOMERS
bond together to form a long chain-like
molecule
 In the case of polythene, the monomer
is the simple ethene molecule

◦ The double bond
allows this molecule
to easily bond with
other like molecules
H
H
C
H
12-52
C
H
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Vinyls

This group of polymers also begins with
the ethene monomer, but with a slight
alteration
◦ One of the hydrogen atoms is replaced by
another atom or group of atoms to form a
VINYL MONOMER

There are a wide variety of vinyl
polymers with a wide variety of
applications to product production
◦ Including polystyrene (Styrofoam)
12-53
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Table 12-3
12-54
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Replacing More Hydrogen Atoms
The next step in complexity for polymer
molecules is the replacement of a
second hydrogen on the ethene
monomer with another atom or group
of atoms
 Example: methacrylate

◦ Marketed under the trade names Lucite and
Plexiglas
◦ This polymer has had tremendous impact
on a variety of human activities due to its
ease of manufacture, light weight,
transparency and durability
12-55
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Other Important Polymer Groups

Teflon

Copolymers

Elastomers

All types of synthetic fibers use to produce
carpets, clothing, and fabrics of all kinds.
◦ Monomer: tetrafluorethene (all H atoms have
been replaced by fluorine atoms)
◦ Widely used for non-stick coatings and in
applications where chemical inertness is
required
◦ Example: Dynel
used in fiber manufacture
◦ These monomers contain some double bonds
◦ Example: neoprene, an elastic fabric material
12-56
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Organic Chemicals and Life Processes
The understanding of nature demands
that we not restrict ourselves to a single
scientific discipline
 The biological world cannot be
separated from the world of the
physical sciences, physics and
chemistry
 Organic chemistry plays an integral role
in the understanding of biological
processes

12-57
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Carbohydrates
The name “carbohydrate” is used to
describe a broad class of molecules
composed of
Carbon
Hydrogen
Oxygen
 They are produced primarily by plant
processes, which use light energy from
the sun as the energy source for a
chemical reaction called photosynthesis

12-58
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Carbohydrates

The term “photosynthesis” provides a
clue about the chemical reaction
occurring in green plants
◦ The reaction is a synthesis reaction whose
product is a long chain molecule
Examples: starches, sugars, cellulose
 These substances provide the source of
energy (i.e., FOOD) for other living
organisms

12-59
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A Word on Sugars


There are several different molecules that
are considered in the class of SUGARS
Monosaccharides (simple sugars)
◦ Glucose
 With isomers FRUCTOSE, GALACTOSE, MANNOSE
 Glucose is the form of sugar circulated in blood

Disaccharides (chains formed from
monosaccharides)
 Examples: Sucrose, lactose, maltose
12-60
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More Complex Sugars



A more complex sugar molecule can be formed from
the combination of more than two simple sugars
One example is
POLYSACCHARIDES
This naturally occurring complex sugar is found as
CELLULOSE
◦ Wood, cotton

Another example is

This special polysaccharide is slightly different in
structure than cellulose
As a food source, the starch molecule is broken down
into a sugar to be usable by living organisms

STARCH
12-61
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Photosynthesis





This amazing endothermic chemical reaction
is responsible for feeding all living organisms,
either directly or indirectly
ENERGY SOURCE: SUNLIGHT
REACTANTS: carbon dioxide (CO2) and water
(H2O)
Neither the CO2 or the H2O directly absorb
the energy from the sun to begin the reaction
A catalyst is necessary for this reaction to
take place
12-62
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The Photosynthesis Catalyst

CHLOROPHYLL
◦ This substance is what contributes to the
green color of most plants
◦ The chlorophyll directly absorbs the energy
from the sun and facilitates the reaction
between the CO2 and the H2O to form the
simple sugar C6H12O6

This simple reaction is responsible for
processing over 70 billion tons of CO2
through plants on a yearly basis
12-63
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Figure 12-21: Photosynthesis
12-64
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Importance of Photosynthesis

Because oxygen is one of the products
produced in the photosynthesis
reaction, this process helps to maintain
the atmospheric oxygen levels,
important for most animal life on the
planet
12-65
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Figure 12-22: Oxygen-Carbon Dioxide
Cycle
12-66
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Organic Calories
Fats, oils, waxes and sterols are
collectively known as LIPIDS
 LIPIDS contain only carbon, oxygen and
hydrogen atoms

◦ The atoms are arranged very differently
than in carbohydrate molecules
12-67
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The Fat Molecule

The general structure of the fat molecule is a
glycerol molecule with three FATTY ACID
molecules bonded to the glycerol

SATURATED fats are those molecules where which
have single bonds

UNSATURATED fats are those molecules with
double bonds between two or more of the carbon
atoms in the structure

POLY UNSATURATED means more than one
double bond per molecule
12-68
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Hydrogenation of Fats


The discover of this process revolutionized
the packaged food industry
In the hydrogenation process, a hydrogen
atom is bonded to double bonded carbon
atoms
◦ This SATURATES the previously unsaturated
molecule

The benefit of this process is that those
unsaturated fats which are normally liquid
at room temperature become solidified at
room temperature
12-69
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Proteins
Every living cell contains protein
 Proteins contain carbon, hydrogen,
oxygen, nitrogen

◦ And sometimes sulfur, phosphorous and
other elements
The “monomer” for building a protein
chain is called an AMINO ACID
 Typical protein molecules are VERY
large, with most containing several
hundred carbon atoms!

12-70
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Protein Function

Depends on both sequence and structure
◦ Both the order (sequence) and arrangement (structure)
of amino acids in a protein molecule are important in
determining the function of a protein

The amino acid groups are linked together with
PEPTIDE BONDS, forming POLYPEPTIDE CHAINS.
◦ These chains are generally folded or coiled in a specific
way, depending on the amino acids

The specific arrangement determines how the
protein will interact in its biological setting
12-71
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Amino Acids for Plants

All amino acids contain nitrogen atoms
◦ Since plant sources are ultimately the starting
point for the food chain, formation of amino
acids and then protein in plants is key to
understanding life processes

The nitrogen needed to form amino acids
in plants must come from the soil, rather
than the surrounding atmosphere
◦ The nitrogen gas in the atmosphere is strongly
bonded
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Nucleic Acids
These organic acids are critically
important for all life processes
 Nucleic acid molecules are composed of
NUCLEOTIDES

◦ With the arrangement of these nucleotides
governing the behavior of the acid molecule
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The Building Blocks of Nucleotides

Each nucleotide consists of three
components
◦ PHOSPHATE GROUP (PO4)
◦ PENTOSE SUGAR
a sugar which contains 5 carbon atoms
◦ NITROGEN BASE
these have characteristic nitrogen-carbon
ring structures
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RNA and DNA
Both RNA and DNA are nucleic acids
 DNA: deoxyribonucleic acid

◦ The pentose sugar for DNA is deoxyribose
◦ The nitrogen bases found in DNA are
adenine, guanine, cytosine, thymine

RNA: ribonucleic acid
◦ The pentose sugar in RNA is ribose
◦ The nitrogen bases found in RNA are
adenine, guanine, cytosine, uracil
12-75
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The Discovery of DNA
Watson and Crick discovered the double
helix structure of DNA in 1953
 DNA molecules are the largest known
molecules, but are usually folded up to
form microscopic packages
 The importance of DNA and RNA in
living organisms is tremendous

◦ DNA controls the function of every cell in
every living thing
◦ RNA carries the detailed instructions
needed for the synthesis of DNA
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Figure 12-27:
DNA Structure
12-77
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Origin of Life


It is believed that it was the formation of
the first amino acid that brought about life
to this planet
In 1952, Miller and Urey performed an
important scientific experiment
◦ They placed the “raw ingredients” that are required
for the production of amino acids into a closed vessel
 Water vapor, hydrogen, methane and ammonia
◦ They then passed electric spark through the mixture
◦ They showed that amino acids could be formed
simultaneously under their conditions
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Figure 12-32: The Miller-Urey Experiment
In a simple
experiment,
Miller-Urey
demonstrated
that it was
possible that
amino acids
formed from
the chemicals
present, with
electric sparks
providing
activation
energy
12-79
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Organic Chemistry: Summary




Organic Chemistry is chemistry of carboncontaining compounds
Structural formulas give information about the
numbers of each atom and the bonding between
them
Isomers are compounds that have varied
structural formulas but identical compositions
Carbon atoms can bond with single, double or
triple covalent bonds. Saturated compounds
contain only single bonds; unsaturated
compounds contain one or more double or triple
bonds
12-80
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Organic Chemistry: Summary (2)

Functional group: a group of atoms that determines the
behavior of an organic molecule
◦ Example: carboxyl group (COOH)

Polymer: long chain of monomers (Plastics)

Carbohydrates are composed of C, H, O and are produced
by green plants in the PHOTOSYNTHESIS process (sugars,
starches, cellulose)

Lipids (fats): synthesized from carbohydrates

Protein is the principal constituent of all living matter;
consists of long chain amino acids

DNA and RNA are nucleic acids; consist of long chains of
nucleotides
12-81
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In-Lecture Quiz
Questions Chapter 12
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In-Lecture Quiz Questions Chapter 12

Those molecules that contain only
single carbon-carbon bonds are called
A.
B.
C.
D.
polycarbonates.
unsaturated.
saturated.
carbony
12-83
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In-Lecture Quiz Questions Chapter 12

The natural gas used for fuel in many
homes is composed primarily of
A.
B.
C.
D.
butane.
methane.
pentane.
ethane.
12-84
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In-Lecture Quiz Questions Chapter 12

The benzene molecule is easy to
identify because
A. atoms. it is a ring with 4 carbon
atoms.
B. it is an infinite number of carbon
atoms in a ring formation.
C. it is a ring of 6 carbon atoms.
D. it is a helix of carbon
12-85
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In-Lecture Quiz Questions Chapter 12

All living cells contain mostly
A.
B.
C.
D.
carbohydrates.
protein.
lipids.
ethane.
12-86
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In-Lecture Quiz Questions Chapter 12

In the photosynthesis reaction, what
serves as the catalyst?
A.
B.
C.
D.
chlorophyll
protein
green dye
benzene
12-87
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In-Lecture Quiz Questions Chapter 12

Those organic compounds that do
NOT contain a benzene ring structure
are called
A.
B.
C.
D.
aromatic.
aliphatic.
elliptic.
nucleic.
12-88
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In-Lecture Quiz Questions Chapter 12

Which of the following statements is NOT
true regarding the carbon atom?
A. Carbon has a valence structure suitable
for combinations with MANY other
atoms.
B. Carbon can form MANY different stable
bonding structures.
C. Carbon has a full outer shell of
electrons.
12-89
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In-Lecture Quiz Questions Chapter 12

Which of the following statements are NOT
true regarding compounds that consist only
of carbon and hydrogen?
A. The chemical behavior of these compounds can
be altered by changing the arrangement of atoms,
even with the same composition
B. These compounds are called hydrocarbons.
C. These compounds come in all phases: solids,
liquids and gaseous.
D. None of the above.
12-90
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In-Lecture Quiz Questions Chapter 12

Organic chemicals are the “chemicals of
life.”
A. True
B. False
12-91
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In-Lecture Quiz Questions Chapter 12

The process by which most beverage
ethanol is produced is called
A. nucleosynthesis.
B. photosynthesis.
C. fermentation.
D. distillation.
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