E-42 Environmental E-42 Environmental ChemistryChemistry

About this “E”…About this “E”…In the following slides, you will learn about how In the following slides, you will learn about how chemical elements and compounds are involved chemical elements and compounds are involved

in the following environmental issues:in the following environmental issues:

On the Ground:On the Ground:1.1. Heavy Metal Heavy Metal

PoisoningPoisoning2.2. Radon (Rn)Radon (Rn)

In the Air:In the Air:1.1. Air Pollution/SmogAir Pollution/Smog2.2. Acid RainAcid Rain3.3. The Greenhouse Effect/Global The Greenhouse Effect/Global

WarmingWarming4.4. Ground Level Ozone/Ozone HoleGround Level Ozone/Ozone Hole

Solutions:Solutions:1.1. RecyclingRecycling2.2. Alternative Alternative

EnergyEnergy

Heavy Metal PoisoningHeavy Metal Poisoning

Examples of Heavy Metals:Examples of Heavy Metals: Lead (Pb)Lead (Pb)

Cadmium (Cd)Cadmium (Cd) Mercury (Hg)Mercury (Hg)

Chromium (Cr)Chromium (Cr)

Mad as a Hatter? … In Alice and Wonderland the Mad Hatter was based on the Victorian hat makers who went “crazy” from long term

exposure to the mercury used to soften beaver fur for hats.

What Are Heavy Metals? … Heavy metals are toxic metals found in the transition metals section of the Periodic Table (See the

examples below.).

How You Can Protect Your Family From Heavy Metal Poisoning … Check your home for lead based paint and

professionally remove or repair cracked paint and paint chips; Do not purchase or use mercury thermometers or other mercury

instruments; and gather all items containing heavy metals and take them to a hazardous waste facility.

The Effects of Heavy Metals on People … general body toxicity, metabolic problems, learning and memory problems, permanent

brain damage, and, even, death!!!

Lead Lead (Pb)(Pb)

Mercury (Hg)Mercury (Hg)

Radon (Rn)Radon (Rn)Where its found …Where its found … in the granite bedrock under much of the United States.in the granite bedrock under much of the United States.

An Invisible Killer … radon is a colorless, odorless gas.How You Can Protect Your Family From Radon

Poisoning? … Have your home tested for radon. If it is discovered, install the appropriate ventilation systems.

The Effects of Radon on People … radon combines with atmospheric dust and then sticks to lung tissue where it is believed to play a significant role in causing lung cancers.

The Chemical The Chemical Composition Composition

of the Atmosphereof the AtmosphereMost Abundant ElementsMost Abundant Elements Nitrogen (N)Nitrogen (N) Oxygen (OOxygen (O22)) Argon (Ar)Argon (Ar)

Most Abundant Most Abundant CompoundsCompounds

(More than one element)(More than one element) Carbon dioxide (COCarbon dioxide (CO22))

Water Vapor (HWater Vapor (H22O)O)

Important note: The composition of air is usually given for dry air because water vapor content in air varies greatly from place to place

and by season (Air can range from less than 1% to more than 4% water vapor.).

Air Pollution … AKA SmogAir Pollution … AKA Smog

Air pollution – harmful substances that get into the air (ex. carbon monoxide (CO), carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen oxides (NO2, N2O4), hydrocarbons(CnH2n+2), lead (Pb), and mercury (Hg)). The burning of fossil fuels and automobile exhaust are major sources of air pollution. Air pollution can cause asthma,

allergies, lung disease, and even death in humans!

Temperature inversion – a dangerous condition in which a layer of colder, polluted air is trapped below a layer of warm air and

cannot disperse. This happens in California where polluted Pacific air becomes trapped near the surface causing smog (NO2).

Rain Gone Bad … Acid Rain Gone Bad … Acid Rain!!!Rain!!!

All rain is somewhat naturally acidic, but when chemicals from car and factory exhaust (CO, CO2, NO, NO2, N2O4 SO,

SO2) combine with rainwater (H2O), they can produce HIGHLY acidic rains (H2CO3) that damage buildings and

monuments and kill plants and fish (ex. H2O + CO2 → H2CO3).

Did you know…99% of the mass

of the atmosphere is located within 32 km (20 miles)

of the Earth’s surface!!!

Mount Everest, the highest

elevation above sea level, is only

about 8.8 km high, keeping it in the bottom layer of

the atmosphere.

Layers of the Atmosphere 1

The Earth's atmosphere is composed of several layers: We live in the Troposphere where Global Warming/The Greenhouse Effect takes place and almost all weather occurs (ex. wind, clouds,

fog, rain, hail, sleet, snow and storms).

Above the Troposphere is the Stratosphere, which contains the Ozone Layer, which blocks out harmful UV rays.

Commercial airliners (ex. a 747) usually fly in the troposphere, whereas supersonic jet airliners (ex. the Concorde) fly in the lower

stratosphere.

Layers of the Atmosphere Layers of the Atmosphere 22

Troposphere Greenhouse Gases trap infrared rays (heat) in here causing Global

Warming.All weather change occurs here. Temperature within this layer decreases as altitude increases because there is an increase in

distance from the warming effect of sunlight absorbed by the Earth’s

surface.

StratosphereThe Ozone Layer absorbs harmful UV Rays here, explaining another

unexpected increase in temperature.

MesosphereColdest layer of the atmosphere.

ThermosphereLower region called ionosphere.Upper region called exosphere.

Nitrogen and oxygen atoms absorb deadly gamma and X rays here,

explaining the unexpected increase in temperature.

The Electromagnetic The Electromagnetic SpectrumSpectrum

Important note:Important note: The shorter the wavelength, the more energetic the The shorter the wavelength, the more energetic the wavelength is and the more harmful the wave is to human tissue!!!wavelength is and the more harmful the wave is to human tissue!!!

Types of Waves in the

Electromagnetic Spectrum (from

highest to lowest energy):

1.Gamma Rays 2.X Rays

3.Ultraviolet 4.Visible light

5. Infrared 6.Microwaves 7.Radio waves

8.TV waves

Infrared Radiation: Heat!Infrared Radiation: Heat!

When infrared rays pass through an object, When infrared rays pass through an object, you feel them as warmth or heat.you feel them as warmth or heat.

Infrared rays heat rocks, soil, water and other Earth Infrared rays heat rocks, soil, water and other Earth materials on the ground. materials on the ground.

These heated objects reradiate longer wavelengths of These heated objects reradiate longer wavelengths of infrared radiation. These longer wavelengths of radiation infrared radiation. These longer wavelengths of radiation

are then trapped by the carbon dioxide and water vapor in are then trapped by the carbon dioxide and water vapor in the Earth’s atmosphere on their way back up into the sky.the Earth’s atmosphere on their way back up into the sky.

Outgoing Radiation and Outgoing Radiation and The Greenhouse EffectThe Greenhouse Effect

Greenhouse EffectGreenhouse Effect – – the process by which visible light and shorter waves of infrared the process by which visible light and shorter waves of infrared

radiation enter the Earth’s atmosphere from the Sun, strike radiation enter the Earth’s atmosphere from the Sun, strike the Earth’s surface, are reradiated as longer wavelengths of the Earth’s surface, are reradiated as longer wavelengths of infrared radiation, and are then trapped by carbon dioxide infrared radiation, and are then trapped by carbon dioxide

(CO(CO22) and water (H) and water (H22O) vapor in the atmosphere.O) vapor in the atmosphere.

Do You like summer?This trapping of heat causes the Earth’s surface and troposphere

(the bottom layer of the atmosphere) to be warmer than if there was no atmosphere at all.

The Greenhouse Effect: the Big The Greenhouse Effect: the Big PicturePicture

The Global Warming: Many The Global Warming: Many FactorsFactors

Manmade (ex. the burning of hydrocarbon fossil fuels, CCnnHH2n+22n+2) and natural (ex. volcanic eruptions) releases of “Greenhouse gases”

into the atmosphere may increase temperatures on the Earth over the next century, leading to the melting of glaciers; disruptions in weather patterns, climate zones, and habitats; increasingly severe storms; massive coastal flooding; and crop failures unless the Earth can compensate (by storing carbon dioxide in rocks and seashells

and by encouraging the growth of more photosynthetic organisms).

UV Rays … Energetic and UV Rays … Energetic and Harmful!!!Harmful!!!

Since they have relatively short, fairly energetic wavelengths, Since they have relatively short, fairly energetic wavelengths, ultraviolet or UV rays are the harmful to humans …ultraviolet or UV rays are the harmful to humans …

Ozone (OOzone (O33) in the stratosphere absorbs most UV waves before they ) in the stratosphere absorbs most UV waves before they reach the Earth’s surface.reach the Earth’s surface.

Ozone (O3): Important Substance in the AtmosphereOzone (O3) is a form of

oxygen found in the stratosphere.

Before Earth had an ozone layer, all life lived under the

oceans … NONE could live above them!

Ozone absorbs harmful ultraviolet radiation (UV

rays) coming from the sun. Ultraviolet radiation can

cause severe burns, cancers, mutations, and even death! Ozone can be destroyed by:

CFC propellants in old aerosol spray cans, Freon

coolant from refrigerants in old refrigerators and air

conditioners, and the burning of supersonic aircraft fuel.

Ozone is created when ultraviolet radiation (UV Ozone is created when ultraviolet radiation (UV rays) from the Sun strikes and splits oxygen rays) from the Sun strikes and splits oxygen

molecules (Omolecules (O22) to atomic oxygen (O). ) to atomic oxygen (O).

The atomic oxygen (O) quickly combines with The atomic oxygen (O) quickly combines with further oxygen molecules to form ozone (Ofurther oxygen molecules to form ozone (O33):):

O2 +

light ->

O + O(1)

O + O2 ->

O3 (2)

Ozone: a Little Chemistry

It should be noted that ground level ozone, which is produced by hydrocarbons that react with sunlight, is a

pollutant itself.

Ground level ozone causes SERIOUS lung irritation!!!

CFCs are chemicals that interfere in this ozone making CFCs are chemicals that interfere in this ozone making process.process.

RecyclingRecycling BiodegradableBiodegradable – things that can be broken down – things that can be broken down

quickly in the natural environment (ex. egg shells, quickly in the natural environment (ex. egg shells, apple and potato peels, and string.)apple and potato peels, and string.)

NonbiodegradableNonbiodegradable – things that remain in the – things that remain in the environment for long periods of time unchanged (ex. environment for long periods of time unchanged (ex.

plastic, glass, and steel.)plastic, glass, and steel.) RecyclingRecycling – saving and reusing materials (See – saving and reusing materials (See

examples below.).examples below.).

Materials that can be recycled:

Paper (organic compound)

Cardboard (organic compound)

Plastics (organic compounds)

Glass (based on SiO2)Aluminum (Al)

Steel (an iron alloy)

All of the following can be All of the following can be recycled…recycled…

Alternative EnergyAlternative Energy

Sources of Alternative Energy:Sources of Alternative Energy: Wind PowerWind Power

Water PowerWater Power Hydrothermal PowerHydrothermal Power

Solar PowerSolar Power

Running Out of Gas? … Most experts agree that we will run out of fossil fuels in our lifetime, even if we don’t, alternative energy would free us from the rising cost of petroleum based

fuels and the politics that accompany them…

More On Wind Power …More On Wind Power … A Source We A Source We Can Use Here!Can Use Here!

Wind power is one of several potential sources of Wind power is one of several potential sources of cleaner, alternative energy. cleaner, alternative energy.

At our latitude (approximately 40°N), wind power might be At our latitude (approximately 40°N), wind power might be able to supply a substantial fraction of the energy we need able to supply a substantial fraction of the energy we need

to generate electricity.to generate electricity.The Equator and 30The Equator and 30 latitude contain the areas called the latitude contain the areas called the

doldrums and the horse latitudes which contain doldrums and the horse latitudes which contain unpredictable winds. As a result, wind turbines would not unpredictable winds. As a result, wind turbines would not

be a reliable alternate energy source for these areas.be a reliable alternate energy source for these areas.

Mid American Energy is now

collecting money to create wind farms

to meet OUR energy needs here in the

QCA!!!

The End!The End!