CHEM CH 2
Nail polish remover containing acetone was spilled in a room 7.83 m × 5.88 m × 5.36 m. Measurements indicated that 5,650 mg of acetone evaporated. Calculate the acetone concentration in micrograms per cubic meter.
2.29+-2%x10 4+-2%
Green chemistry is
the design of products and processes that reduce hazardous substances.
At high concentrations, nitrogen monoxide will directly react with oxygen to produce nitrogen dioxide, but in the atmosphere, its production is more complex.
true
nitrogen dioxide
-produced at high temperature reactions between oxygen and nitrogen gasses in engines and power plants -causes respiratory irritation and distress -creates brown smog -is produced through natural processes on earth as well as by humans
Which component of the air is an element? Group of answer choices
O2
parts per billion (ppb)
Sulfur dioxide in the air should not exceed 30 ppb = 30 sulfur dioxide molecules 1 x 10^9 molecules and atoms in air
N2O = dinitrogen monoxide (also known as nitrous oxide, or laughing gas)
true
Nitrogen monoxide is produced when nitrogen & oxygen are exposed to high heat.
true
Ozone
-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 as humans
carbon monoxide
-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 as by humans
Levels of Air Quality Index
0-50 good, green 51-100 moderate, yellow 101-150 unhealthy for sensitive groups, orange 151-200 unhealthy, red 201-300 very unhealthy, purple 301-500 hazardous, maroon
For the 1-hour average value, a city reports 0.180 ppm ozone. The permissible limit is 0.120 ppm ozone. By what amount, in ppm, does the reported value exceed the 0.120 ppm ozone? By what percent does the reported value exceed the permissible limit?
0.060 ± 2% ppm 50 ± 2% %
Which of the following are common units of concentration used when reporting the level of common air pollutants? Select all that apply. Multiple select question.
ppb ppm μg/m3
One complex pathway to nitrogen dioxide requires the presence of VOCs and ·OH (a free radical).
true
Prefixes are used to designate the number of each type of element:
true
If 500 mL of air contains 2 × 1022 particles (atoms and molecules), how many particles do you inhale in one day if you breathe 15000 L of air?
6 x 10^26
The air exhaled from the lungs of a smoker has a concentration of 750 ppm CO. Express the concentration as a percent.
.0750%
Which of the following statements correctly describe different forms of matter? Select all that apply.
- Both mixtures and pure substances are forms of matter -Mixtures can consist of any four phases of matter.
If air is composed of 78% nitrogen this means that by volume air contains 78 parts nitrogen for every _____ Unavailable parts of air.
100
Provide the proper coefficients (including 1's) required to balance this reaction: ___ CH4(g) + ____O2(g) →→ ___CO2(g) + ___H2O(g)
1CH4(g) + 2O2(g) → 1CO2(g) + 2H2O(g)
How would you express .002 molecules of CO2 per hundred molecules of air as a concentration?
20 parts per million
How many carbon atoms does the molecule octane have?
8
All of these pollutants can be detected by their odors except
CO
Which component of the air makes up approximately 100 times more of an exhaled breath than of an inhaled breath?
CO2
Which of the following are considered air pollutants? Select all that apply.
Carbon monoxide Nitrogen dioxide Ozone Particulate matter
The more toxic the pollutant, the higher the concentration is set when concerning air quality standards.
False
1- mono 2- di 3- tri 4- tetra 5- penta 6- hexa 7- hepta 8- octa 9- nona 10- deca
Naming Binary Compounds
Which correctly pairs an indoor pollutant with its source?
O3 and electrical arcing
In general, which airborne material is not likely to be affected by the filters or indoor air handling equipment?
carbon monoxide
What is the correct name for the following molecular compound: CCl4?
carbon tetrachloride
The _______ _____ symbolically represents the type and number of each element present.
chemical formula
the rapid reaction of fuel with oxygen to release
combustion
Ammonia (NH3) is a
compound
Carbon Dioxide (CO2) is a
compound
Table salt (NaCl) is a
compound
Water (H2O) is a
compound
Fluorine (F2) is a
element
Nickel (Ni) is a
element
the amount of the substance encountered
exposure
Cheaper and less wasteful ways to produce consumer products.
green chemistry
Limiting or eliminating the use of organic solvents.
green chemistry
Paints that contain fewer volatile organic compounds (VOCs)
green chemistry
Plastics synthesized from renewable sources instead of typical fossil-fuel derived precursors.
green chemistry
Removing arsenic from the touchscreens of portable electronic devices.
green chemistry
Chemists use three viewpoints to study and understand matter, _______, _________, and _______.
macroscopic, symbolic, and particulate.
Which color, as used in the Air Quality Index, warns that the level of a pollutant is hazardous, the most dangerous level?
maroon
parts per million (ppm)
midday ozone levels reach about 0.4ppm
Sea water (salts dissolved in water) is a
mixture
Soap (various organic compounds) is a
mixture
_______ is a physical combination of two or more species
mixture
A ______ is a fixed number of atoms held together by chemical bonds in a certain spatial arrangement.
molecule
largest component of the air is
nitrogen
the composition of air is a mixture
nitrogen (78%) Oxygen (21%) Other gases (1%)
______ form of matter with a definite composition
pure substance
In the process of ______, the foods that we eat are metabolized to produce carbon dioxide, water, and energy.
respiration
Equal volumes of gases contain equal numbers of atoms or molecules, as long as the samples are at the same _____ and _____
temperature, pressure
intrinsic health hazard of a substance
toxicity
the intrinsic health hazard of a substance
toxicity
The risks presented by air pollutants are a function of what thing(s)? Select all that are correct
toxicity and exposure
lowest region of the atmosphere
troposphere
Catalytic converters reduce the amount of carbon monoxide (CO) in the exhaust due to catalyzing the combustion of carbon monoxide to carbon dioxide (CO2)
true
Chemical reactions are characterized by the rearrangement of atoms when reactants are transformed into products. This is an example of a combustion reaction.
true
Hydrocarbons are compounds containing only carbon and hydrogen atoms
true
Which of the following species are the two products of respiration?
water and carbon dioxide
Of five major gaseous components of air, which is the only one to vary significantly in concentration from place to place and from day to day?
water vapor
These gases represent the most harmful for our health and the health of our planet:
-Carbon monoxide -Ozone -Sulfur dioxide (SO2) -Nitrogen dioxide (NO2)• - -Particulate matter (PM)
sulfur dioxide
-SO2 -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 as by humans
The EPA limit for CO is 9 ppm. Express this number as a percentage.
.0009%
For the 1-hour average value, a city reports 0.180 ppm ozone. The permissible limit is 0.120 ppm ozone. By what amount, in ppm, does the reported value exceed the 0.120 ppm ozone? By what percent does the reported value exceed the permissible limit?
0.060 ± 2% ppm 50%
There are approximately 2 × 1022 molecules and atoms in each breath we take and the concentration of CO in the air is approximately 9 parts per million. Approximately how many CO molecules are in each breath we take?
1.8 x 10^17
How many carbon atoms does the hydrocarbon decane contain? Number of carbons =
10
Express this concentration in terms of ppm: 0.0347%
347ppm
A sample of cigarette smoke contains 2.08% carbon monoxide. The U.S. national ambient air quality standard for CO in a 1-hr period is 35.0 ppm.How many times greater than this standard is the CO concentration in cigarette smoke?
600
Which of the following options correctly describe the troposphere? Select all that apply. Multiple select question. 75% of our air is found within the troposphere. Air currents and storms occur in the region of the atmosphere just above the troposphere. An inversion layer in the troposphere occurs when cooler air is trapped below warm air. The warmest air in the troposphere is about 6 miles from the surface of the Earth. The troposphere is the region of the atmosphere in which humans live.
75% of our air is found within the troposphere. An inversion layer in the troposphere occurs when cooler air is trapped below warm air. The troposphere is the region of the atmosphere in which humans live.
Parts per hundred (percent)
Atmosphere 21% Oxygen=21 Oxygen molecules/100 Molecules and atoms in air
What is the greatest source of indoor air pollution in developing countries?
Cookstoves
C2H6
ethane
Ozone is a secondary pollutant. A secondary pollutant is
not produced directly but as the product of the interaction of two or more pollutants.
Ozone is a secondary pollutant. A secondary pollutant is Group of answer choices
not produced directly but as the product of the interaction of two or more pollutants.
75% of our air, by mass, is in the troposphere, the lowest region of the atmosphere in which we live.
true
P2O5 = diphosphorus pentoxide
true
The energy from sunlight splits the nitrogen dioxide to oxygen and nitrogen monoxide.
true
The free oxygen atoms in turn react with oxygen to form ozone.
true
Balance the following chemical equation: N2 + O2 ⟶ NO2 , by giving the correct coefficients for the N2, O2 and NO2 respectively.
1,2,2
Choose the proper coefficients for each substance to balance this equation.___ C2H4(g) + ___ O2(g) → ___ CO2(g) + ___ H2O(g)
1,3,2,2
The Air Quality Index (AQI) is scaled from ___ - ___ .
1-500