CHEMISTRY AND THE ENVIRONMENT Flashcards
Formation of the Atmosphere
1. _________
4.5 Million years ago, the atmosphere was composed of Hydrogen, Helium, Ammonia and Methane,
similar to the atmosphere of Saturn and Jupiter today
2. ___________
Volcanic activity from the Earth’s solid crust released gases such as water vapor, carbon dioxide
and ammonia, similar to the atmosphere of Mars and Venus today
As the Earth grew cooler, water vapor formed into clouds creating rain, which resulted to
formation of the _______
_______ was formed from the breakdown of ammonia due to sunlight
Other gases formed were hydrogen, methane, and carbon monoxide in trace amounts, with
hydrogen sulfide (H2S), sulfur dioxide (SO2), and chlorine
Primitive Atmosphere
Secondary Atmosphere
ocean
Nitrogen
Formation of the Atmosphere
3. _______
Oxygen was produced from
a. dissociation of water vapor by strong _________
b. Photosynthesis of ___________
c. ____________ of metals present in the Earth’s surface
Oxygen molecules started absorbing UV radiations resulting to the formation of ______ Formation of O3 made life on Earth possible
. Oxidizing Atmosphere
ultraviolet radiation
cyanobacteria
Oxidation
ozone
(O3)
___________
➢ thick mixture of gases surrounding the Earth’s surface
➢ serves as a shield used to protect life, making our planet unique
➢ mixture of gases is forced to remain near the Earth’s surface due to gravity
➢ decrease in atmospheric material is observed with increase in altitude, until it gradually
reaches outer space
___________
➢ an imaginary line which identifies the boundary between the atmosphere and outer space
Atmosphere
Karman Line
Year of Discovery Element/Compound Discovered by
1750s Carbon dioxide _______
1766 Hydrogen ____________
1772 Nitrogen ____________
1774 Oxygen __________ and
1772 (published in 1777) _______
1840 Ozone ____________
1894 Argon _____________
Joseph Black
Henry Cavendish
Daniel Rutherford
Joseph Priestly
Carl Wilhem Scheele
Christian Friedrich Schonbein
Lord Rayleigh and William Ramsay
Year Scientist Discovery
1924 ____________Developed a spectrophotometer and started measurements of totalcolumn ozone
1930 ___________ Described the theory that explains the existence of the ozone layer
1960 ____________ Described the emergence of the photochemical smog
1973 _________ First detected chlorofluorocarbons (CFCs) in the Atmosphere
1995
___________
___________
____________
Awarded jointly the Nobel Prize in Chemistry for their work in
atmospheric chemistry, particularly concerning the formation and
decomposition of ozone
Gordon Dobson
Sydney Chapman
Arie Jan Haagen-Smit
James Lovelock
Paul Crutzen
Mario Molina
Frank Sherwood Rowland
Atmospheric Composition
Atmospheric gases are generally classified by their _____________
___________
the average amount of time that a gas spends in the atmosphere
It can be estimated as the amount of the compound in the atmosphere divided by the rate at which
this compound is removed from the atmosphere
amount and residence time.
Residence Time
Composition of the Atmosphere as Percent by Volume of Gases
Nitrogen _______
Oxygen _______
Argon _____
Carbon
Dioxide ______
Trace Gases ________
78.08%
20.95%
0.934%
0.035%
0.001%
Atmospheric Gases
_________
an inert gas fundamental to all living systems
Removed from the atmosphere through a process called _______ wherein
atmospheric N2
is reduced to form ammonia.
can be “fixed” or removed by soil bacteria or by lightning during precipitation.
can be returned to the atmosphere by biomass combustion and denitrification.
________ – the reduction of nitrates to gaseous nitrogen by microorganisms in a
series of biochemical reactions
NITROGEN
nitrogen fixation
Denitrification
Atmospheric Gases
_________
exchange between the atmosphere and biosphere is realized by
_______________.
________
third most abundant gas in the atmosphere.
OXYGEN
photosynthesis and respiration
ARGON
Atmospheric Gases
____________
is mostly concentrated on the lower atmosphere (about 90% of total atmospheric water
vapor found in the lower ______ atmospheric layer, and 99% of it found in the ________
_________ the capacity of air to hold water vapor dependent solely of air
temperature. The higher the temperature, the __________ that can be
held without condensation.
important for radiation and energy budgets of the atmosphere, and in the formation of
clouds and precipitation
absorbs about 70% of the incoming shortwave solar radiation, and about 60% of outgoing
long-wave radiations, making it the ___________
___________ – describes the net flow of energy into the Earth which is mainly in the
form of shortwave radiation and infrared longwave radiation
WATER VAPOR
5 km
troposphere
Saturation Level
greater amount of water vapor
most significant greenhouse gas.
Energy/Heat Budget
Atmospheric Gases
_____________
an important greenhouse gas since it has a strong absorption capacity of infrared and
near-infrared radiation
it is continually exchanged between the atmosphere and biosphere through
____________
Some of atmospheric CO2 are dissolved by the _________.
increase in CO2 levels has been observed due to growing industries and human
activities, like burning of fossil fuels, deforestation, and other forms of land-use
change. Man-made activities like these contributed to global warming with the
increase of the greenhouse effect
CARBON DIOXIDE
photosynthesis and respiration
seas and oceans
________
a chemical compound of hydrogen and oxygen
contains strong covalent bonds that hold two
hydrogen atoms and one oxygen atom together
bonded as H-O-H with a bond angle of 105°
between the two hydrogen atoms in liquid
water and a large angle of 109° 6’ for ice
Three isotopes of hydrogen and three of
oxygen exist in nature, therefore _______ varieties
of water molecules are possible
WATER
18
WATER
electrons are ______ shared between the
oxygen and hydrogen atoms
hydrogen atoms are slightly ______ in charge
while the oxygen atom is slightly negative in
charge, forming hydrogen bonds
___________ – a weak bond between
polar compounds where hydrogen atom of one
molecule is attracted to an electronegative
atom of another molecule. Water can form up
to _ hydrogen bonds
unequally
positive
Hydrogen Bond
4
WATER
expected to be gaseous at room
temperature yet due to the
many hydrogen bonds it
contains, it is ____.
Liquid water has higher
coordination number than _____
__________ – the
average number of nearest neighbor
atoms with respect to a central
atom
liquid.
ice
Coordination Number
CHEMISTRY OF WATER
WATER
Specific Heat - ______
________ – the energy
required to convert 1 gram of ice to water
at 0 °C, estimated at 80 calories
____________ – the
energy required to convert 1 gram of
liquid water into vapor at 100 °C,
estimated at540 calories
1 cal/g/°C
Latent Heat of Fusion
Latent Heat of Vaporization
CHEMISTRY OF WATER
___________
Substances which can induce physical, chemical, or biological changes to a body of water
SURFACE WATER POLLUTION
___________
➢ Sources that emit pollutants which
directly influences different bodies of
water
➢ examples are domestic and industrial
wastes for these wastes are directly
dumped into bodies of water
___________
➢ sources of water pollution that indirectly affect
bodies of water through environmental changes
➢ example would be contaminated water that
runs off from farms, mines, and construction
sites, affecting bodies of water
➢ more difficult to deal with than point sources
Water Pollutants
Point Sources
Non-Point Sources
SURFACE WATER POLLUTION
__________
➢ an increase in the concentration of naturally occurring substances
➢ Siltation occurs when continuous
deforestation makes soil loose and run-off
water during precipitation bring silt and dirt
from mountain into bodies of water
___________
➢ pollution due to human activities or manmade sources of water pollution
➢ Domestic wastes, such as sewage and waste
water, industrial wastes, and agricultural
wastes are common example
Natural Sources
Anthropogenic Sources
___________
Results from polluted water seeping into the
ground and enters an aquifer
Polluted water such as sewage, nitrogenous
fertilizer, and toxic waste
GROUNDWATER POLLUTION
FACTORS THAT AFFECT WATER QUALITY
- Temperature
- Dissolved Oxygen
- Alkalinity
- Acidity
- Hardness
TEMPERATURE
__________
➢ Formation of distinct layers within nonflowing bodies of water due to
temperature difference
➢ The two layers of a body of water do
not mix, but they behave _______
and have different chemical and
biological properties
Thermal Stratification
independently
_________ - surface layer
➢ constantly exposed to _________, resulting to
higher temperature and lower density, making it
float over the bottom
_________ - layer between the epilimnion and hypolimnion
➢ Heavy growth of algae due to exposure to
atmosphere and sunlight
➢ Contains high levels of dissolved oxygen
__________ – lowest layer
➢ Anaerobic due to consumption of oxygen by
biodegradable organic material
EPILIMNION
solar radiation
THERMOCLINE
HYPOLIMNION
Properties of Water that are affected by
temperature:
1. The ________ that can be dissolved
in the water. Cold water can dissolve
more oxygen than warm water.
2. The rate of __________ of algae
and other aquatic plants.
3. The _________ of aquatic organisms
(respiration, digestion, etc.)
amount of gas
photosynthetic action
metabolism
Changes in Water Temperature is
caused by:
_______________
____________
occurs when water in an entering
stream is warmer than the water
already present in a body of water
Sources: nuclear power plants, which
discharge cooling wate
- Air Temperature
- Thermal Pollution
___________
Needed by aquatic organisms for respiration and decomposition of organic matter
Most fish kills result from low levels of dissolved oxygen
___________
a measure of its capacity to neutralize acids, or
a measure of buffer capacity (greatly used in waste water treatment)
the alkalinity of waters can be attributed to the ___________
___________ contribute the most to the alkalinity of water
DISSOLVED OXYGEN
ALKALINITY
salts of weak acids
Bicarbonates
_________
_________ is acidity due to carbon dioxide dissolved in bodies of water. This is the most common form of acidity in water.
Acidic waters are of major concern because of their _________
ACIDITY
CO2 Acidity
corrosive characteristics
___________
Divalent metallic cations cause the ___________ of water
principal hardness causing cations are calcium, magnesium, strontium, ferrous and manganous
ions
HARDNESS
hardness
________
heterogeneous mixtures of air, water, inorganic and organic solids, and microorganisms (both
plant and animal)
__________ is the branch of science that deals with the chemical composition,
properties and reactions of soils
___________ is the study of chemical reactions between soils and
environmentally important plant nutrients, radionuclides, metals, metalloids, and organic
chemicals
SOIL
Soil Chemistry
Environmental Soil Chemistry
COMPOSITION OF SOIL
Inorganic Components of Soil
______ are formed by the aggregation of sand, silt, and
clay particles to form larger soil structure that result
from the action of soil forming factors
_______ develop in the loose material on the earth’s
surface and are composed of layers of varying texture,
structure, color, bulk density and other properties.
These layers are also of varying thickness
__________ is the smallest unit that can be considered
“soil” and consists of all horizons extending from the
soil surface to the underlying geologic strata. An area
consisting of similar pedons is called a __________
Peds
Profiles
Pedon
polypedon
Inorganic Components of Soil
The elements found in soils with the highest quantities
are the following:
________ - most prevalent element. (47% of the
Earth’s crust by weight and 90% by volume)
Oxygen
a natural inorganic
compound with
definite physical,
chemical and
crystalline properties
MINERAL
CHEMISTRY OF SOIL
_________
a mineral that has not been
chemically altered since its
deposition from molten lava.
Examples: quartz and feldspar,
pyroxenes, micas, amphiboles
and olivines
primarily occur on sand and
silt fractions of soils but may
be found in slightly weathered
clay-sized fractions
PRIMARY MINERAL
CHEMISTRY OF SOIL
_________
the result of the weathering of a
primary mineral, either through
alteration in the structure or from
reprecipitation of the products of
weathering (dissolution) of a
primary mineral
primarily found in the clay fraction
of the soil but can also be found in
the silt fraction
SECONDARY MINERAL
Organic Components of Soil
___________, includes the
total organic compounds in soils, excluding undecayed plant and
animal tissues, their “partial decomposition” products, and soil
biomass
mixture of plant and animal residues in different stages of
decomposition, substances synthesized microbiologically and/or
chemically from the breakdown products, and the bodies of live
and dead microorganisms and their decomposing remains
Soil Organic Matter (SOM) also called humus
___________ Undecayed plant and animal tissues and their partially decomposed products
_________ Organic matter present as live microbial tissue
__________
A series of relatively high-molecular-weight, brown-to-black-colored substances formed
by secondary synthesis reactions.
_________
Compounds belonging to known classes of biochemistry, such as amino acids,
carbohydrates, fats, waxes, resins, and organic acids
________ The alkali insoluble fraction of soil organic matter
__________
The dark-colored organic material that can be extracted from soil by various reagents
and is insoluble in dilute acid
_________ The colored material that remains in solution after removal of humic acid by acidification
__________ Alcohol soluble portion of humic acid
Organic residues
Soil biomass
Humic substances
Nonhumic substances
Humin
Humic acid
Fulvic acid
Hymatomelanic Acid
_____________ of soil humus is the maximum number of moles of proton charge dissociable from unit mass of solid-phase humus under given conditions
of temperature, pressure, and aqueous solution composition, including the humus concentration
**CEC (Cation Exchange Capacity)
SOIL DECONTAMINATION
In Situ Techniques
a. Volatilization
b. Biodegradation
c. Phytoremediation
d. Leaching
e. Vitrification
___________
a. Land Treatment
b. Thermal Treatment
c. Asphalt Incorporation
d. Solidification/Stabilization
Non-In Situ Techniques
