Organic Compounds and
Everyday Life
2.4
You are already aware that organic compounds are an inescapable part of
your daily life. As you know, much of your body is composed of organic
compounds. The food you eat is made from organic compounds, as are the
clothes you wear. The fuel that heats your home and powers buses and
cars is also organic. When you are sick or injured, you may use organic
compounds to fight infection or to reduce pain and swelling. Modern
processed foods include many flavourings and colourings—another use
of organic compounds. (See Figure 2.23.)
Section Preview/
Specific Expectations
CH3
In this section, you will
■
discuss the variety and
importance of organic
compounds in your life
■
analyze the risks and benefits of the production and
use of organic compounds
■
explain how organic chemistry has helped to solve
problems related to human
health and the environment
OH
H3C
CH
CH3
menthol
Figure 2.23 In Chapter 1, you learned about esters that are used as flavourings. Not all
flavourings belong to the ester family. Menthol is an organic compound that is found in the
mint plant. It is used as a flavouring in many substances, including toothpaste, chewing gum,
and cough syrups. What functional group is present in menthol? How might you guess this
from the name?
In this section, you will examine the uses of some common organic
compounds. You will also carry out an analysis of some of the risks and
benefits that are involved in making and using organic compounds.
Risk-Benefit Analysis
How can you make the most informed decision possible when analyzing
the risks or benefits of a product or issue? The following steps are one
way to carry out a risk-benefit analysis for the manufacture and use of an
organic compound.
Step 1 Identify possible risks and benefits of the organic product. Ask
questions such as these:
• What are the direct uses of this product? (For example, is it used
as a pharmaceutical drug for a specific disease or condition? Is it
an insecticide for a specific insect “pest”?)
• What are the indirect uses of this product? (For example, is it used
in the manufacture of a different organic or inorganic product?)
• What are the direct risks of making or using this product?
(For example, is the product an environmental pollutant, or does
it contain compounds that may be harmful to the environment?
Can the workers who manufacture this product be harmed by
exposure to it?)
Chapter 2 Reactions of Organic Compounds • MHR
97
• What are the indirect risks of making or using this product? (For
example, are harmful by-products produced in the manufacture
of this product? How much energy does the manufacture of this
product require, and where does the energy come from? What, if
any, side effects does this product cause?)
Step 2 Research the answers to your questions from step 1. Ensure that
your information comes from reliable sources. If there is controversy
on the risks and benefits of the product, find information that covers
both sides of the issue.
Step 3 Decide on your own point of view. In your opinion, are the benefits
greater than the risks? Do the risks outweigh the benefits?
Step 4 Consider possible alternatives that may lessen the risks. Ask
questions such as the following:
• Does a similar, less harmful, product exist?
• Is there a better way to manufacture or dispose of this product?
• What safety precautions can be taken to reduce the risks?
Risks and Benefits of Organic Compounds
The next four tables outline common uses of various organic compounds,
as well as possible complications resulting from each use. The
ThoughtLab that follows provides an opportunity for you to work with
and extend the information in the tables. Of course, the compounds listed
are only a few of the many useful organic compounds that are available to
society.
Table 2.4 Uses and Possible Complications of Selected Pharmaceutical Drugs
Source
Common uses
salbutalmol
(Ventolin®)
• developed from ephedrine,
a compound that occurs
naturally in the ma huang
(ephedra) plant
• used as asthma medication
• possible side effects
include tremors, nausea,
heart palpitations,
headaches, and
nervousness
lidocaine
• developed from cocaine, a
compound that occurs
naturally in the coca leaf
• used as a local anaesthetic,
in throat sprays and
sunburn sprays
• possible side effects
include skin rash or
swelling
morphine
• occurs naturally in the
opium poppy plant, which
is still the simplest and
cheapest source of
morphine
• one of the strongest
pain-killers known
• highly addictive
• possible side effects
include dizziness,
drowsiness, and breathing
difficulty
acetylsalicylic acid
(A.S.A., Aspirin®)
• developed from salicin,
found in the bark of the
willow tree
• reduces fever,
inflammation, and pain
• used to prevent heart
attacks by thinning blood
• possible side effects
include stomach upset
• more rare side effects
include stomach bleeding
and Reye’s syndrome
acetaminophen
(Tylenol™)
• developed from acetyl
salicylic acid
• reduces fever and pain
• possible side effects
include stomach upset
• can cause liver damage in
high doses
Organic compound
98
MHR • Unit 1 Organic Chemistry
Side effects and /or concerns
Table 2.5 Uses and Possible Complications of Selected Pesticides
Pesticide
Common uses
Side effects and /or concerns
parathion
• insecticide
• kills insects by disrupting
their nerve impulses
• one of the most toxic
organophosphate pesticides
• highly toxic to humans,
birds, aquatic invertebrates,
and honeybees
carbaryl
• insecticide
• similar to parathion, but
safer for humans
• more expensive than
parathion
• generally low toxicity to
humans and most other
mammals
• highly toxic to fish, aquatic
invertebrates, and honey
bees
endrin
• insecticide
• also controls rodents, such
as mice
• persists in soil up to
12 years
• highly toxic to fish
• banned in some countries
and restricted use in many
others
pyrethrin
• natural pesticide
• breaks down quickly in the
environment
• irritating to skin, eyes,
respiratory system
• highly toxic
• can be dangerous to
humans and pets within
range of the pesticide
application
• very toxic to aquatic life
resmethrin
• synthetic pyrethroid
pesticide
• 75 times less toxic to
humans and pets than
pyrethrin
• low toxicity to humans and
other mammals (causing
skin, eye, and respiratory
system irritation)
• irritating to skin, eyes, and
respiratory system
• highly toxic to fish and
honey bees
Table 2.6 Uses and Possible Complications of Selected Food Additives
Organic Compound
Common uses
Side effects and /or concerns
aspartame
• artificial sweetener
• significant controversy over
possible health risks
menthol
• flavouring in many
substances, including
toothpaste, chewing gum,
and cough syrups
• may cause allergic reaction
MSG
(monosodiumglutamate)
• flavour enhancer for foods
• may cause allergic reaction
known as MSG symptom
complex, with symptoms
such as nausea and
headache
• may worsen already severe
asthma
Red #40
• food colouring
• may cause allergic reaction
Chapter 2 Reactions of Organic Compounds • MHR
99
Table 2.7 Uses and Possible Complications
of Selected Common Organic Compounds
Organic compound
tetrachloroethene • solvent used to dry-clean
(Perc™)
clothing
ThoughtLab
Side effects and /or concerns
Common uses
• toxic
• may damage central
nervous system, kidneys,
and liver
ethylene glycol
• automobile antifreeze
• toxic, especially to small
pets and wildlife
• may damage central
nervous system, kidneys,
and heart
acetone
• nail polish remover
• industrial solvent
• highly flammable
• irritating to throat, nose,
and eyes
Risk-Benefit Analyses of Organic Products
As you know, organic products provide many of the
necessities and comforts of your life. They are also
responsible for a great deal of damage, including
environmental pollution and harm to human health.
In this Thought Lab, you will perform risk-benefit
analyses on three organic compounds.
Procedure
1. Choose three of the organic compounds listed in
Tables 2.4 through 2.7. Research and record the
chemical structure of each compound.
2. Follow the four steps for a risk-benefit analysis,
given at the beginning of this section. You will
need to carry out additional research on the
compounds of your choice.
Analysis
1. What are the practical purposes of this organic
compound?
2. (a) What alternative compounds (if any) can be
used for the same purpose?
(b) What are the benefits of using your particular
compound, instead of using the alternatives
in part (a)?
3. (a) What are the direct risks of using this
compound?
(b) What are the indirect risks of using this
compound?
4. In your opinion, should this compound continue
to be used? Give reasons for your answer.
5. What safety precautions could help to reduce
possible harm— to people as well as to the
environment —resulting from this compound?
For each compound, answer the following
questions.
Problem Solving With Organic Compounds
Many chemicals and products have been developed as solutions to health,
safety, and environmental problems. Sometimes, however, a solution to
one problem can introduce a different problem. Read the three articles on
the next few pages. Then complete the ThoughtLab that follows.
100 MHR • Unit 1 Organic Chemistry
Replacing CFCs—At What Cost?
At the beginning of the twentieth
century, refrigeration was a
relatively new technology. Early
refrigerators depended on the
use of toxic gases, such as
ammonia and methyl chloride.
Unfortunately, these gases sometimes leaked from refrigerators,
leading to fatal accidents. In 1928,
a new, “miracle” compound was
developed to replace these toxic
gases. Dichlorodifluoromethane,
commonly known as Freon®, was a
safe, non-toxic alternative. Freon®
and other chlorofluorocarbon
compounds, commonly referred to
as CFCs, were also used for
numerous other products and
applications. They were largely
responsible for the development of
many conveniences, such as airconditioning, that we now take for
granted.
Today we know that CFCs
break up when they reach the
ozone layer, releasing chlorine
atoms. The chlorine atoms destroy
ozone molecules faster than the
ozone can regenerate from oxygen
gas. Studies in the past ten years
have shown dramatic drops in
ozone concentration at specific
locations. Since ozone protects
H3C
CH
CH3
Earth from the Sun’s ultraviolet
radiation, this decrease in ozone
has led to increases in skin cancer,
as well as damage to plants and
animals. In addition, CFCs are
potent greenhouse gases and contribute to global warming. Through
the Montréal Protocol, and later
“Earth Summit” gatherings, many
countries—including Canada—
have banned CFC production.
Substitutes for CFCs are
available, but none provide a
completely satisfactory alternative.
Hydrofluorocarbons (HFCs) are
organic compounds that behave
like CFCs, but do not harm
the ozone layer. For example,
1,1,1,2-tetrafluoroethane
and
1,1-difluoroethane are HFCs that
can be used to replace CFCs in
refrigerators and air conditioners.
Unfortunately, HFCs are also
greenhouse gases.
Simple hydrocarbons can also
be used as CFC substitutes.
Hydrocarbons such as propane,
2-methylpropane (common name:
isobutane), and butane are efficient
aerosol propellants. These hydrocarbons are stable and inexpensive,
but they are extremely flammable.
CH3CH2CH3
CH3CH2CH2CH3
propane
butane
CH3
isobutane
F
H
F
C
C
H
F
F
1,1,1,2-tetrafluoroethane
F
F
H
C
C
H
H
H
1,1-difluoroethane
Chapter 2 Reactions of Organic Compounds • MHR
101
Revisiting DDT: Why Did it Happen?
Dichlorodiphenyltrichloroethane,
better known as DDT, is a wellknown pesticide that has caused
significant environmental damage.
It is easy to point fingers, blaming
scientists and manufacturers for
having “unleashed” this organic
compound on an unsuspecting
world. It is more difficult, however,
to understand why this environmental disaster took place.
Insects consume more than
one third of the world’s crops each
year. In addition, insects such as
mosquitoes spread life-threatening
diseases, including malaria and
encephalitis. Weeds reduce crop
yields by taking over space, using
up nutrients, and blocking sunlight.
Some weeds even poison the
animals that the crops are intended
to feed. Crop damage and low
crop yield are significant problems
for countries undergoing food
shortages and famines.
DDT was one of the first
pesticides that was developed.
For many years, it was used successfully to protect crops and fight
disease epidemics. Paul Mueller,
the scientist who discovered
DDT’s use as a pesticide, was
awarded the Nobel Prize in 1948.
Cl
Cl
CH
C
Cl
Cl
Cl
DDT
Later, however, tests revealed that
DDT does not readily decompose
in the environment. Instead, DDT
remains present in the soil for
decades after use. The hydrocarbon
part of this molecule makes it soluble in the fatty tissues of animals.
As it passes through the food
chain, DDT accumulates. Animals
that are higher in the food chain,
such as large birds and fish, contain
dangerous concentrations of this
chemical in their tissues. A high
DDT concentration in birds causes
them to lay eggs with very thin
shells, which are easily destroyed.
Today DDT is no longer produced
or used in Canada. It is still used,
however, in many developing
countries.
Knocking on the Car Door
Automobile fuels are graded using
octane numbers, which measure
the combustibility of a fuel. A high
octane number means that a fuel
requires a higher temperature
and/or higher pressure to ignite.
Racing cars with high-compression
engines usually run on pure
methanol, which has an octane
number of 120.
Gasoline with too low
an octane number can cause
“knocking” in the engine of a car,
when the fuel ignites too easily and
burns in an uncontrolled manner.
Knocking lowers fuel efficiency,
and it can damage the engine.
As early as 1925, two of the
first automobile engineers became
aware of the need to improve the
octane number of fuels. Charles
Kettering advocated the use of a
newly developed compound called
tetra-ethyl lead, Pb(C2H5)4. This
compound acts as a catalyst to
102 MHR • Unit 1 Organic Chemistry
increase the efficiency of the
hydrocarbon combustion reaction.
Henry Ford believed that ethanol,
another catalyst, should be used
instead of tetra-ethyl lead. Ethanol
could be produced easily from
locally grown crops. As we now
know, ethanol is also much better
for the environment.
Tetra-ethyl lead became the
chosen fuel additive. Over many
decades, lead emissions from car
exhausts accumulated in urban
ponds and water systems. Many
waterfowl that live in urban areas
experience lead poisoning. Lead is
also dangerous to human health.
Leaded fuels are now banned
across Canada. In unleaded gasoline, simple organic compounds
are added instead of lead compounds. These octane-enhancing
compounds include methyl-t-butyl
ether, t-butyl alcohol, methanol,
and ethanol. Like lead catalysts,
these compounds help to reduce
engine knocking. In addition, burning ethanol and methanol produces
fewer pollutants than burning
hydrocarbon fuels, which contain
contaminants. Since they can be
made from crops, these alcohols
are a renewable resource.
CH3
H3C
O
C
CH3
CH3
2-methoxy-2-methyl propane
(methyl tert-butyl ether)
CH3
HO
C
CH3
CH3
1,1-dimethyl ethanol
(tert-butyl alcohol)
ThoughtLab
Problem Solving with Organic Compounds
In this ThoughtLab, you will consider several
situations in which organic compounds were used
to help solve a health, safety, or environmental
problem.
(d) Have these additional problems been
resolved? If so, how have they been resolved?
(e) Do you foresee any new problems arising
from the solutions in part (d)? Explain why
or why not.
Procedure
1. Choose two of the situations that are discussed
in the three newspaper articles. Come up with a
third situation, involving organic compounds,
that you have heard or read about recently. For
the three situations you have chosen, answer
the following questions.
(a) What was the original problem?
(b) How was this problem resolved? What part
did organic compounds play in the solution?
(c) What further problems (if any) were
introduced by the solution in part (b)?
Analysis
1. Use your knowledge of organic chemistry to
describe how organic chemistry has helped
to provide a solution to
(a) a human health problem
(b) a safety problem
(c) an environmental problem
2. In your opinion, is it worth coming up with
solutions to problems, if the solutions carry
the possibility of more problems? Explain
your answer.
Section Summary
In this section, you encountered some of the ways that organic compounds
make our lives easier. As well, you learned about some of the risks
involved in using organic compounds. You carried out risk-benefit analyses
on several organic compounds. Finally, you examined some situations in
which organic chemistry has helped to solve problems related to human
health, safety, and the environment.
Section Review
1
MC
Think about the risks and benefits of organic compounds.
(a) Describe five specific benefits you obtain from organic compounds.
(b) Describe two risks from organic compounds, and explain how these
risks may affect you.
2
C Prepare a brochure, booklet, or web page explaining the practical
uses of organic compounds to a younger age group. Your booklet
should include the following information:
• a simple explanation of what an organic compound is
Unit Issue Prep
Before researching your issue
at the end of Unit 1, decide
how you will use the information and skills you learned in
this section. What are some
possible direct and indirect
risks and benefits involved in
the issue you have chosen?
• a description of some benefits of organic compounds
• specific examples of at least three different organic compounds that
you studied in this chapter, plus their uses
• specific examples of at least three different organic compounds that
you did not study in this chapter, plus their uses
Chapter 2 Reactions of Organic Compounds • MHR
103
3
Research persistent organic pollutants (POPs) on the Internet. Use
your research to prepare a poster about POPs for your community.
Include the following information:
C
• examples of three POPs, with descriptions of their negative effects
on the environment and/or human health
• a description of what the Canadian government has done to address
the problem of POPs
• suggestions for ways that your community can avoid or reduce harm
from organic pollutants
4
In section 2.3, you learned about some of the risks and benefits
of polymers. Choose a synthetic polymer from section 2.3. Carry out
a risk-benefit analysis of this polymer.
5
C Scientists and horticulturalists who work with and sell the
synthetic pesticide pyrethroid are concerned about public perception.
Many people buy the natural pesticide pyrethrin, even though it is
more toxic than pyrethroid. Why do you think this happens? Do you
think this happens for other products that have natural and synthetic
alternatives? Write a brief editorial outlining your opinions and advice
to consumers, to help them make informed product choices.
104 MHR • Unit 1 Organic Chemistry
MC