CHM 576 (Environmental Chemistry)

• Tests (3) 30%

• Quizzes 10%
• Assignment 20%
- Presentation – Oral (15%) Written (5%)
• Final Exam (Comprehensive) 40%
100%

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 INTRODUCTION

Topic 1
INTRODUCTION & COMPOSITION AND STRUCTURE
OF THE ATMOSPHERE
 LESSON OUTCOMES FOR TOPIC 1

Students should be able to:

1. Name, explain and give examples of the
different types of resources.
2. Name, identify and explain types and causes
of environmental problems.
3. Name the different layers of the atmosphere.
4. Distinguish composition and structure of the
different layers of the atmosphere.
 INTRODUCTION
• Environment - everything that affects a living
organism (any unique form of life) during its lifetime.

• Ecosystems is a region in which the organisms and

the physical environment form an interacting unit.
Ecosystems can be small or large.
 INTRODUCTION
• Resource – anything obtained from the
environment to meet human needs and wants.
Material resources from the environment can be
classified as perpetual, renewable or
nonrenewable.
• Perpetual resource for example solar energy as it
is renewed continously. It is expected to last at least
6 billion years as the sun completes its life cycle.
• Renewable resource can be replenished fairly
rapidly (hours to several decades) through natural
processes as long as it is not used up faster than it
is replaced . Examples are fresh water, fresh air,
fertile soil and plants and animals (biodiversity).
 INTRODUCTION
Nonrenewable resources – exist in a fixed
quantity or stock in the earth’s crust. These
include energy resources (such as coal, coal,
oil and natural gas which cannot be recycled),
metallic mineral resources (such as iron,
copper and aluminium, which can be recycled),
and nonmetallic mineral resources (such as
salt,clay, sand, and phosphates, which usually
are difficult or too costly to recycle).
 RESOURCES
• Renewable resources can be depleted or degraded.
The highest rate at which a renewable resource can
be used indefinitely without reducing its available
supply is called its sustainable yield.
• If we exceed a resource’s natural replacement rate,
the available supply begins to shrink, a process
known as environmental degradation. Examples
include degradation include urbanization of
productive land, waterlogging and salt buildup in soil,
excessive topsoil erosion, deforestation, groundwater
depletion, overgrazing of grasslands by livestock, and
reduction in the earth’s forms of wildlife (biodiversity)
by elimination of habitats and species and pollution.
 RESOURCES

NONRENEWABLE
ENERGY RESOURCES
coal, oil and natural gas which
cannot be recycled
NONRENEWABLE
Exist in a fixed
quantity or stock in the MINERAL RESOURCES
earth’s crust. Metallic mineral resources (such as
iron, and aluminium, which can be
recycled
RESOURCE
&
anything obtained
from the environment Nonmetallic mineral resources (such as
to meet human needs salt, clay, and sand, which usually are
and wants difficult or too costly to recycle).
RENEWABLE
Can be replenished fairly
rapidly (hours to several
decades) through natural
processes as long as it is RENEWABLE ENERGY
not used up faster than it is RESOURCES
replaced. Solar energy, wind energy
and hydropower

RENEWABLE RESOURCES
fresh water, fresh air, fertile
soil and plants and animals
(biodiversity).
 CULTURE

Definition: The whole of a society’s

knowledge, beliefs, technology and
practices.

Human cultural changes have profound

effects on the environment.
CULTURAL CHANGES

Huntering and Gathering Society

Agricultural Revolution

Agricultural Society
Industrial –Medical Revolution

Industrial-Medical Society
Information &
Communication Revolution
Information and Communication Society
 CULTURAL CHANGES
Three major cultural changes/revolution
have occurred since humans were
mostly hunter-gatherers who obtained
food by hunting wild animals and gathering
wild plants.

➢Agricultural Revolution
Began 10,000 -12,000 years ago when
humans learned to grow and breed plants
and animals for food, clothing and other
purposes.
 AGRICULTURAL REVOLUTION
Agricultural Revolution
Good News Bad News
More food Destruction of wildlife habitats
from clearing forests and
Supported a larger grasslands
population Killing of wild animals feeding
Longer life expectancy on grass or crops
Fertile land turned into desert by
Higher standard of living for livestock overgrazing
many people
Soil eroded streams and lakes
Formation of villages, towns,
and cities Towns and cities concentrated
wastes and pollution and
increased spread of diseases
Towns and cities served as
centers for trade, government,
and religion Increase in armed conflict
and slavery over ownership
of land and water resources
 CULTURAL CHANGES
• Industrial-Medical Revolution
➢Began 275 years ago when people invented
machines for large scale production of goods
in factories.
➢This involved learning how to get energy from
fossil fuels (such as coal and oil) and how to
grow large quantities of food in an efficient
manner.
➢It also included medical advances that have
allowed a growing number of people to live
longer and healthier lives.
 INDUSTRIAL-MEDICAL
REVOLUTION
Industrial-Medical Revolution
Good News Bad News
Mass production of useful
and affordable products Increased air pollution
Higher standard of living Increased water pollution
for many
Increased waste pollution
Greatly increased
agricultural production Groundwater depletion
Lower infant mortality
Habitat destruction and
Longer life expectancy degradation

Increased urbanization
Biodiversity depletion
Lower rate of population
growth
 CULTURAL CHANGES
➢ Information- Globalization Revolution
Began 50 years ago when we developed new technologies for
gaining rapid access to much more information and resources
on a global scale.

❑ Many environmental scientists and other analysts now

call for a fourth major cultural change in the form of a
SUSTAINABILITY REVOLUTION during this century.
This cultural transformation would involve learning how
to reduce our ecological footprints and to live more sustainably.
 Information-Globalization Revolution

Positive Aspects Negative Aspects

Computer-generated models Information overload can

and maps of the earth’s cause confusion and sense
environmental systems of hopelessness

Remote-sensing satellite Globalized economy can

surveys of the world’s increase environmental
environmental systems degradation by
homogenizing the earth’s
surface
Ability to respond to
environmental problems
more effectively and Globalized economy can
rapidly decrease cultural diversity
 OVERALL EFFECT OF CULTURAL
CHANGES ON THE ENVIRONMENT
➢ Gave us more energy and new technologies with
which to alter and control more of the planet to meet
our basic needs increasing wants.
➢ Allowed expansion of the human population, mostly
because of increased food supplies and longer life
spans.
➢ Resulted in greater resource use, pollution and
environmental degradation as they allowed us to
dominate the planet and expand our ecological
footprints.
 ECOLOGICAL FOOTPRINT
• The Ecological Footprint is defined as amount of biologically
productive land and water needed to provide the people in a
particular country or area with an indefinite supply of
renewable resources and to absorb and recycle the wastes
and pollution produced by such resource use.

• The per capita ecological footprint is the average ecological

footprint of an individual in a given country or area. It is an
estimate of how much of the earth’s renewable resources an
individual consumes.

• If a country’s (or the world’s) total ecological footprint is larger

than its biological capacity to replenish its renewable
resources and to absorb the resulting wastes and pollution, it
is said to have an ecological deficit. In other words, it is living
unsustainably by depleting its natural capital instead of living
off the income provided by such capital. Natural capital are
the natural resources and natural services that keep us and
other forms of life alive and support our human economies.
ECOLOGICAL FOOTPRINT
ECOLOGICAL FOOTPRINT
ECOLOGICAL FOOTPRINT
 If the ecological footprint per person of a country or of the world is larger than its
biological capacity per person to replenish its renewable resources and absorb the
resulting waste products and pollution, the country or the world is said to have an
ecological deficit/debit (-). If the reverse is true, the country or world has an ecological
credit or reserve(+)
 ENVIRONMENTAL SUSTAINABILITY
• Living sustainably means living off natural income
replenished by soils, plants, air and water and not depleting
the earth’s natural capital that supplies this income.

• Many environmentalists and leading scientists believe we

are living unsustainably by depleting and degrading the
earth’s natural capital at an accelerating rate as our
population and demands on the earth’s resources and life–
sustaining processes increase exponentially.
 Natural Capital
Solar Natural Capital = Natural Resources + Ecosystem Services
energy

Air
Renewable
Air purification energy (sun,
wind, water
Climate control flows)
UV protection
(ozone layer) Life
(biodiversity)

Water Population
control
Water purification
Pest
Waste treatment control

Nonrenewable Soil Land

minerals
(iron, sand) Soil renewal Food production
Nutrient
recycling
Nonrenewable
energy
(fossil fuels)

Natural resources
Ecosystem services Fig. 1-3, p. 7
 Natural Capital Degradation
Degradation of Normally Renewable Natural Resources

Shrinking
Climate forests
change
Decreased
wildlife
Air pollution habitats
Species
extinction
Soil erosion
Water
pollution

Declining ocean
fisheries
Aquifer
depletion

Fig. 1-7, p. 11
 ENVIRONMENTAL PROBLEMS

FIVE MAJOR
ENVIRONMENTAL PROBLEMS

Food
Biodiversity Waste Water Air
Supply
Depletion Production Pollution Pollution
Problems
CAUSES OF ENVIRONMENTAL PROBLEMS

Unsustainable Poverty Excluding Increasing

Population environmental costs
resource use isolation
growth from market prices from nature

Fig. 1-15, p. 16
ENVIRONMENTAL SUSTAINABILITY
• Environmental Sustainable Society
– tries to achieve two goals.
First, it satisfies the basic needs of its
people for food, clean water, clean air and
shelters into the indefinite future.
Second, it does this without depleting or
degrading the earth’s natural resources
and thereby preventing current and future
generations of humans and other species
from meeting their basic needs.
 A MORE SUSTAINABLE FUTURE IS
POSSIBLE
• Making a shift toward a more sustainable
future will involve some tough challenges.
• However, here are two pieces of good
news:
• First, research by social scientists
suggests that it takes only 5-10% of the
population of a community, a country or
the world to bring about major change.
 A MORE SUSTAINABLE FUTURE IS
POSSIBLE
• Second, such research also shows that
significant social change can occur in a
much shorter time than most people think.
• Anthropologist Margaret Mead
summarized our potential for social
change: “ Never doubt that a small group
of thoughtful, committed citizens can
change the world. Indeed it is the only
thing that ever has.
 SUSTAINABILITY
 To learn how to live more sustainably and thus more
wisely, we need to find out how life on earth has
sustained itself. There seem to be three themes
relating to the long term sustainability of life on this
planet:
Reliance on solar energy,
Biodiversity
Chemical cycling.
 These three interconnected scientific principles of
sustainability (reliance on solar energy, biodiversity and
chemical cycling) are derived from learning how nature
has sustained a huge variety of life on earth for at least
3.5 billion years, despite drastic changes in
environmental conditions.
THREE SCIENTIFIC PRINCIPLES OF SUSTAINABILITY

Solar Energy

Reliance on solar energy

Chemical Cycling Biodiversity

 THREE STRATEGIES FOR REDUCING
OUR ECOLOGICAL FOOTPRINTS
• Based on the three scientific principles of sustainability, we can
derive three strategies for reducing our ecological footprints.

➢ Rely more on renewable energy from sun, including indirect

forms of solar energy such as wind and flowing water to meet
most of our heating and electricity needs.

➢ Protect biodiversity by preventing the degradation of the

earth’s species, ecosystems and natural processes, and by
restoring areas we have degraded.

➢ Help to sustain the earth’s natural chemical cycles by

reducing the production of wastes and pollution, not
overloading natural systems with harmful chemicals, and not
removing natural chemicals faster than nature’s cycles can
replace them.
Some Examples of
Renewable Energy
 SOLAR THERMAL SYSTEMS

Solar thermal power: This solar power plant (left) in a California desert uses curved
(parabolic) solar collectors to concentrate solar energy to provide enough heat to boil
water and produce steam for generating electricity. In another type of system (right),
an array of mirrors tracks the sun and focuses reflected sunlight on a central receiver
to boil the water for producing electricity. Fig. 16-15, p. 416
SOLAR CELLS

Fig. 16-18, p. 418

In Japan, Kyocera Corp. and Century Tokyo Leasing Corp. and have started building a 13.7-megawatt
floating solar plant on the Yamakura Dam reservoir near Tokyo. The plant is scheduled for launch in
March 2018.
 With some 70 lakes found suitable in Peninsular Malaysia for developing floating photovoltaic (PV)
systems, Tenaga Nasional Bhd (TNB) has just embarked on its a 100kWp pilot system in Sg Labu Water
Treatment Plant in Sepang, Selangor. The project, which is owned by the Ministry of Energy, Green
Technology and Water, is 80% funded by the Malaysia n Elect ricit y Supply Industries Trust Account or
known by its Malay acronym AAIBE (Akaun Amanah Industri Bekalan Elektrik), while the rest is by TNB.
The RM3.95 million project will span around 1,000 sq m over a 50ha lake. The pilot floating PV systems
project commenced in March 2015 and is scheduled for completion by November 2016.
Trade-Offs

Wind Power

Advantages Disadvantages

High net energy Needs backup or

yield storage system when
winds die down
Widely available
Visual pollution for
Low electricity some people
cost
Little or no direct Low-level noise
emissions of CO2 bothers some people
and other air
pollutants
Can kill birds if not
Easy to build properly designed
and expand and located

Fig. 16-25, p. 423

Trade-Offs
Solid Biomass

Advantages Disadvantages
Widely available Contributes to
in some areas deforestation
Moderate costs
Clear-cutting can
Medium net cause soil erosion,
energy yield water pollution, and
loss of wildlife habitat
No net CO2
increase if
Can open
harvested,
ecosystems to
burned, and
invasive species
replanted
sustainably
Increases CO2
Plantations can emissions if harvested
help restore and burned
degraded lands unsustainably
Fig. 16-26, p. 424
WE CAN CONVERT PLANTS AND PLANT
WASTES TO LIQUID BIOFUELS
• Liquid biofuels such as ethanol (ethyl alcohol
produced from plants and animal wastes)
and biodiesel (produced from vegetables oils)
are being used to fuel motor vehicles.
• U.S produces ethanol from corn.
• Brazil produces ethanol from sugarcane.
• European union produces mainly biodiesel
from vegetable oil.
• China produces mostly ethanol from non-
grain plant sources to divert grains from its
food supply.
• Malaysia produces biodiesel from palm oil.
 2. Heat from underground spins
a turbine to power a generator
and produce electricity

Generator
Steam turbine
Heat
exchanger 3. Steam from turbine condenses
to water and is pumped back
down to geothermal reservoir

Production well Injection well

1. Hot water or steam is pumped
under pressure to the surface
from underground

Geothermal
reservoir

Fig. 16-30a, p. 428

Trade-Offs

Large-Scale Hydropower

Advantages Disadvantages

High net energy Large land

yield disturbance and
displacement of
Large untapped people
potential
High CH4 emissions
Low-cost
from rapid biomass
electricity
decay in shallow
tropical reservoirs
Low emissions of
CO2 and other air
pollutants in Disrupts downstream
temperate areas aquatic ecosystems

Fig. 16-22, p. 420

 Electrons

Hydrogen Anode
Polymer
gas (H2) in electrolyte
A fuel cell takes in membrane
hydrogen gas and
separates the
hydrogen atoms’
Cathode
electrons from
their protons. The
electrons flow
through wires to
provide
electricity, while
the protons pass
through a Water vapor
membrane and
combine with (H2O) out
oxygen gas to
form water vapor.

Protons

Air (O2) in
Fig. 16-32, p. 430
PROTECTING
BIODIVERSITY
We can participate in biodiversity
conservation by increasing our knowledge of
environmental issues, increasing our
awareness of the impacts of biodiversity loss,
and increasing support for government
policies and actions that conserve our
valuable ecosystems.

We can become educators and role models

as stewards of the environment by aiding in
the recovery of species at risk and preventing
other species from becoming at risk
BIOGEOCHEMICAL/NUTRIENT
CYCLES
Nesa (Dec-Apr09)
STRUCTURE OF THE
ATMOSPHERE
Topic 1
 Atmosphere
• Layer of gases surrounding the planet and retained by
the earth’s gravity.
• Density and atmospheric pressure vary throughout the
atmosphere.
• Most of the atmosphere is held close to the earth by the
pull of the gravitational force, so it gets less dense with
increasing distance from the earth.

Composition of the Atmosphere

• The atmosphere is primarily composed of nitrogen (N2,
78%), oxygen (O2, 21%), and argon (Ar, 1%).
• A myriad of other very influential components are also
present which include the water, "greenhouse" gases,
ozone and carbon dioxide.
 Composition of Atmosphere
Chemical
Gas Name Percent Volume
Formula
Nitrogen N2 78 %
Oxygen O2 21%
*Water H2O 0 to 4%
Argon Ar 1%
*Carbon Dioxide CO2 0.04%
Neon Ne 0.002%
Helium He 0.001%
*Methane CH4 0.0002%
Hydrogen H2 0.0001%
*Nitrous Oxide N2O 0.00003%
*Ozone O3 0.000004%
 Structure of the Atmosphere
• Atmosphere can be divided into 5 different
regions or layers

1. Troposphere
2. Stratosphere
3. Mesophere
4. Thermosphere
5. Exosphere

• The boundaries between spheres are called

tropopause, stratopause, mesopause and
thermopause.
Layers of the Atmosphere
Layers of the Atmosphere
 Troposphere
• The inner layer of the atmosphere
• Extends about 17 km above sea level at the
equator and 8 km over the poles.
• Contains about 75% of the mass of the earth’s
air.
• The temperature decreases with increasing
altitude which leads to relatively rapid mixing of
atmospheric components.
• This thin and turbulent layer of rising and falling
air currents and winds is the earth’s weather
breeder.
• Layer of atmosphere involved in the chemical
cycling of the earth’s vital nutrients.
• The troposphere contains most of the water
vapour of the atmosphere.
 Stratosphere
• Atmosphere’s second layer. Located on top of
troposphere.
• Extends for about 17 km - 48 km above earth’s surface
and contains most of the ozone.
• Stratospheric ozone acts like a ‘global sunscreen’ and it
keeps about 95% of the sun’s harmful UV radiation from
reaching the earth’s surface.
• This UV filter allows us and other forms of life to exist on
land and helps protect us from sunburn, skin and eye
cancer, cataracts and damage to our immune system
• This UV filter also prevents much of the oxygen in the
troposphere from being converted to
photochemical/tropospheric ozone, a harmful air pollutant.
 Stratosphere
• Volume of water vapour is about 1000 times less than
the troposphere.
• Volume of ozone is 1000x the troposphere.
• The temperature increases with increasing altitude which
inhibits vertical mixing.
Mesosphere
• Third layer of the atmosphere, extends from 48 km to 85
km above the stratosphere.
• Layer in which a lot of meteors burn up while entering
the earth’s atmosphere.
• The air is relatively mixed together and the temperature
decreases with altitude.
• Atmosphere reaches its coldest temperature of around -
900C in the mesophere.
 Thermosphere
• Fourth layer of the earth’s atmosphere, located
above the mesosphere. Extends from 85 km to
600 km.
• Air is really thin in the thermosphere.
• Small change in energy causes a large change
in temperature. Temperatures can go as high as
17000C.
• Thermosphere also includes the region of
atmosphere called the ionosphere which is a
region filled with charged particles.
• Different regions of the ionosphere make long
distance radio communication possible by
reflecting the radio waves back to earth.
• Astronauts orbiting Earth in the space station or
space shuttle spend their time in this layer.
 Exosphere
• The atmosphere merges into space in the
extremely thin exosphere. This is the
upper limit of our atmosphere and is called
the exosphere.
• The exosphere is the outermost layer of
the atmosphere and extends from the
thermopause to 6,200 miles (10,000 km)
above the earth.
• In this layer, atoms and molecules escape
into space.