CHM 1020 chapter 2
Given the ample supply of oxygen, hydrocarbon fuels burn completely. You may hear this called
"complete combustion"
The Pollution Prevention Act is focused on
preventing the formation of hazardous substances, stating that "pollution should be prevented or reduced at the source whenever feasible"
One naturally occurring air pollutant of concern is a ___, a noble gas
radon
ozone is a bad actor in the troposphere because even at very low connections, it
reduces lung function in healthy people who are exercising outdoors. Ozone also damages crops and the leaves of trees.
___ ___ is the process of evaluating scientific data and making predictions in an organized manner about the possibilities of an outcome
risk assessment
particulate matter is visible as
soot or smoke
Candles deplete the oxygen in a room. They also produce
soot, carbon monoxide, and VOCs
It has been named as a "command and control law" or an "end of the pipe solution," because it tries to limit the
spread of hazardous substances or clean them up after the fact
what type of pollutant has these characteristics -produced from the burning of sulfur containing fuels such as coal -causes respiratory irritation and distress -produces acid rain -is produced through natural processes on earth as well by humans -a sharp and unpleasant odor -comes primarily from the burning of coal
sulfur dioxide
About 75% of our air, by mass, in the troposphere, the lowest region of the atmosphere in which we live that lies directly above the
surface of Earth
Depending on where you live, you will breathe air of varying quality because
these differences arise from a number of factors such as population, regional activities, geographical features, prevailing weather patterns, and the activities of people in neighboring regions
Vehicles do not emit sulfur dioxide because
they have internal combustion engines primarily fueled by gasoline.
Converting from parts per million to parts per billion involves moving the decimal point
three places to the right
particulate matter is another air pollutant that is a complex mixture of
tiny solid particles and microscopic liquid droplets
The layers of Earth include:
troposphere -> stratosphere -> mesosphere -> thermosphere
(true or false) The percentages we have been using to describe the composition of the atmosphere are based on volume-the amount of space that each gas occupies. The result mixture is 78% nitrogen, 21% oxygen, and 1% argon The composition of air can also be represented in terms of the numbers of molecules and atoms present. Thus, if you were able to take a sample of air containing 100 particles, 78 would be nitrogen molecules, 21 would be oxygen molecules, and 1 would be an argon atom
true
true or false Air pollutants can also accumulate in the cooler air of inversion layer
true
true or false An organic compound always contains carbon, almost always contains hydrogen, and may contain other elements such as oxygen and nitrogen
true
true or false CO has an appreciably long atmospheric lifetime to move freely in and out buildings through doors, windows, or a ventilation system. The same is true for some VOCs, but not for the more-reactive ones such as those that give pine forests their scent
true
true or false Paint formulations once contained lead but are now banned and they banned lead-containing compounds from motor vehicle gas
true
what are the characteristics of a chemical equation
-must be balanced on both sides -never touch the subscripts of the chemicals
what are the characteristics of radon
-odorless -tasteless -chemically unreactive -radioactive
With each breath, we inhale air to obtain ___, and we exhale ___ into the
-oxygen -carbon dioxide
For relatively low concentrations, it is more convenient to use ___ ___ ___. One ppm is a unit of concentration that is 1/10,000 the size of 1%
-parts per million (ppm)
ozone does not come out of a ___, and is not produced when ___ is burned
-pipeline -coal
Combustion is a type of chemical reaction, a process whereby substances described as ___ are transformed into different substances called ___
-reactants -products
ozone is a ____ ____ that is produced from ___ ___ involving one or more other pollutants
-secondary pollutant -chemical reactions
the Air Quality Index (AQI) of orange indicates
-the air has become unhealthy for some groups -(100-150)
the Air Quality Index (AQI) of green or yellow indicates
-the air is good or moderate quality -(< 100)
the Air Quality Index (AQI) of red, purple, or maroon indicates
-the air is unhealthy for everyone to breathe -(> 150)
The risks presented by an air pollutant are a function of both ___, the intrinsic health hazard of a substance, and ___, the amount of the substance encountered
-toxicity -exposure
Whether at high or low concentration, ___ is a colorless, odorless gas that is invisible to the eye. These formations are actually not composed of water vapor. Rather, they consist of tiny droplets of ___ or ___
-water vapor -water; crystal ice
the color-coded Air Quality Index (AQI) is called from
1 to 500
A catalyst is a chemical substance that participates in
a chemical reaction and influences its rate, without itself undergoing permanent change
If the humidity is high enough, they help condense water vapor into an ___ of tiny water droplets
aerosol
___ is colorless, odorless gases that are invisible to the eye and undetectable to the nose
air
in the troposphere, ___ ___ occur when cooler air gets trapped beneath warmer air due to weather conditions in an area
air inversions
The waste that we stash in our atmosphere is called ___ ___
air pollution
___ ___ refers to the air surrounding us, usually meaning the outside air
ambient air
The law of conservation of matter and mass means
atoms are neither created nor destroyed in a chemical reaction
However, radon may reach hazardous levels in
basements, mines, and caves
The internal combustion of hydrocarbon in gasoline produces
carbon dioxide and water vapor
what type of pollutant has these characteristics -produced by incomplete combustion of fuels such as gasoline, diesel, and propane -sometimes called "the silent killer" this gas prevents hemoglobin from carrying oxygen in the blood stream -is produced through natural processes on earth as well by humans -it has no color, taste, or smell
carbon monoxide
Gases contribute to air pollution are
carbon monoxide, ozone, sulfur dioxide, and nitrogen dioxide
In addition to vehicles producing carbon dioxide and water vapor, they also add
carbon monoxide, volatile organic compounds, nitrogen oxides, and particulate matter
Volatile organic compounds (VOCs) are
carbon-containing compounds that pass easily into the vapor phase
Gas particles can move around and "through" one another. This means that trace amounts of substances can be
carried in the air
A chemical equation is a representation of a ___ ___ using chemical formulas
chemical reaction
Some systematic names which are not determined by the following set of rules because
chemists gave a name to the compound before understanding the rules
___ is the chemical process of burning; that is, the rapid reaction of fuel with oxygen to release energy in the form of heat and light
combustion
Unlike systematic names, ___ ___ cannot be figured out by simply looking at the chemical formula. You have to know them or look them up
common names
Exposure depends on factors that we can measure more easily such as
concentration in the air, length of time, and rate of breathing
list examples of air pollution
cooking meals over fire or driving combustion engine vehicles
in the troposphere, ___ ___ is found higher up, a phenomenon you may have observed if you have hiked or driven to higher elevations
cooler air
People cook with solid fuels (wood, crop waste, animal dung, or coal) in their homes over open fires and simple stoves. This occurs primarily in
developing countries
Earth's ___ ___ is what actually keeps these gases from escaping our atmosphere, creating a virtual "container" of gases around Earth's surface
gravitational pull
what calls for designing chemical products and processes that reduce or eliminate the use or generation of hazardous substances
green chemistry
The warmest air in the troposphere usually lies at ___ ___ because the Sun's rays penetrate the air and primarily heat the ground, which, when reflected from the surface, warms the air above it
ground level
In some cases, poor ventilation can cause indoor pollutants to reach ___ levels, creating a condition known as "sick building syndrome"
hazardous
Given the increasing number of vehicles any decrease in NOx and CO emissions is
impressive
The decrease in NOx and CO emissions is due to several factors, including
improved engine design, computerized sensors that better adjust the fuel-oxygen mixture and most importantly, the requirement that all cars manufactured since the mid-1970s have catalytic converters
For highly reactive molecules such as O3, NO2, and SO2, you should expect lower levels
indoor
The goal of green chemistry is to use
less energy, create less waste, use fewer resources, and use renewable resources
U.S Clean Air Act led to the establishment of air quality standards such as focusing on
limiting our exposure to hazardous substances
aerosol are
liquid and solid particles that remain suspended in the air rather than settling out
Temperature fluctuations exist across these levels, and overall pressure decreases the farther away from Earth due to the
lower amounts of gases at each higher level
if aerosol is inhaled, the droplets of the sulfuric acid aerosol are small enough to become trapped in the
lung tissue and cause several damage
sustainability means
making decision with a concern not only for today's outcomes, but also for the needs of future generations
lead is another air pollutant and it comes from sources such as
mental processing plants, waste incinerators, and plumbing materials, as well as lead-acid battery manufacturing and recycling facilities
The air we breathe is a
mixture
Two major sources of air pollutants:
motor vehicles and coal-fired that generate electricity
Radion is a special case of indoor pollution, because it occurs
naturally in tiny amounts and usually is no problem
People may not necessarily agree on which standards of air quality are reasonable and safe, and standards may change over time as ___ ___ ___ is generated or as political decisions change
new scientific knowledge
what type of pollutant has these characteristics -produced at high temperature reactions between reactions between oxygen and nitrogen gasses in engines and power plants -causes respiratory irritation and distress -produces acid rain -creates brown smog -is produced through natural processes on earth as well as by humans -is a colorless gas
nitrogen dioxide
what type of pollutant has these characteristics -is a colorless gas -it is formed from the reaction of N2 and O2 in the air from anything that is hot, including vehicle engines and coal-fired power plants
nitrogen monoxide
The pure substances that are in air:
nitrogen, oxygen, argon, carbon dioxide, and water
The chemical names and formulas (known as ___) of the compounds relating to the air you breathe
nomenclature
When you are writing a chemical formula for a name, remember that the subscript of 1 is ___ ___ in chemical formulas
not shown
In the process called respiration, we take in ___ to help metabolize the foods we eat
oxygen
what type of pollutant has these characteristics -produced as a secondary pollutant by the reaction of nitrogen dioxide with sunlight and oxygen -causes respiratory irritation and distress -beneficial in the upper atmosphere but harmful in the lower atmosphere -is produced through natural processes on earth as well by humans -It has a sharp odor that you can detect around electric motors or welding equipment
ozone
A building that is airtight with a limited intake of fresh air may have ___ ___ of indoor air pollutants
unhealthy levels
Particulate matter originates from many sources, including
vehicle engines, coal-burning power plants, wildfire, and blowing dust.
Burning candles or incense can generate fumes more rapidly than they can be removed by your
ventilation system or by the breezes that pass through open windows
Because sunlight is involved in ozone formation, the concentration of ground-level ozone varies with
weather, season, and latitude
The composition of air by volume is about ___ nitrogen, ___ oxygen, and ___ other gases. Percent means "parts per hundred"
-78% -21% -1%
what is the chemical equation for the complete combustion of methane (unbalanced and balanced)
-CH4 + O2 -> CO2 + H2O (unbalanced equation) -CH4 + 2 O2 -> CO2 + 2 H2O (balanced equation)
what are the rules for writing molecular compounds (compounds composed of two or more nonmetal)
-Name each element in the chemical formula, modifying the name of the second element to end in -ide -Use prefixes to indicate the numbers of atoms in the chemical formula -If there is only one atom for the first element in the chemical formula, omit the prefix mono-
examples of using green chemical methods
-Plastics synthesized from renewable sources instead of typical fossil fuel-derived precursors -Paints that contain fewer volatile organic compounds -Cheaper and less wasteful ways to produce pharmaceuticals, pesticides, and consumer products, such as contact lenses and disposable diapers -Limiting or eliminating the use of organic solvents for dry cleaning and electronics fabrication processes -Removing arsenic from the touchscreens of portable electronics
Sugar and oxygen are transformed into ___ and ___, and ___ is made available to carry out other essential processes in our bodies
-carbon dioxide and water -energy
A volatile substance readily passes into the vapor phase; that is, it
evaporates easily
these tinier and more deadly particles from particulate matter are sometimes called
fine particulates
Many air-handling systems contain filters that remove
larger-sized particulate matter and pollen
Gas molecules such as O3, CO, and NO2, and SO2 are not trapped by
the filters used in most ventilations