CHM 1020 Chapter 2

nitrogen oxides

-brown color and is the primarily visible component of urban smog -formed from the reaction of N2 and O2 in the air from anything that is hot, including vehicle engines and coal fired power plants -natural and manmade causes respiratory irritation and distress -acid rain

particulate matter

-complex mixture of tiny solid particles and microscopic liquid droplets -classified by size rather than composition -originate from vehicle engines, coal burning power plants, wildfires, and blowing dust -comes in a range of sizes but only the tiny particles (Pm 10 & Pm 2.5) are regulated as pollutants

three factors of pollutant exposure

-concentration in the air -length of time -rate of breathing

always conserved in a chemical equation

-identity of atoms in reactants=identity of atoms in products -number of atoms of each exempt in reactant=number of atoms of each element in products -mss of all reactants=mass of all products

systematic naming rules

-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

radon

-naturally occurring air pollutant -occurs naturalizing in tiny amounts and usually is no problem, however, it may reach hazardous levels in basements, mines, and caves -colorless, odorless, tasteless, and chemically unreactive -is radioactive! -is generated in the decay series of uranium

may change in a chemical equation

-number of molecules in reactants may differ from the number of products -physical states of reactants may differ fro those of products

ozone

-sharp odor -detected around electric motors or welding equipment -secondary pollutant by the reaction of NO2 with sunlight and oxygen -causes respiratory irritation and distress -natural and manmade

sulfur dioxide

-sharp unpleasant odor -from burning coal and released by volcanoes -can lead to the formation of aerosols -can react with water to produce acid rain -causes respiratory irritation and distress -natural and manmade

carbon monoxide

-the silent killer because it has no color, taste, or smell - from automobile exhaust & charcoal/wildfires fires -produced by incomplete combustion -natural and manmade

methane

1 carbon atom

how ozone is produced

1. nitrogen monoxide is produced when nitrogen and oxygen are exposed to high heat 2.at high concentrations, nitrogen monoxide will direct react with oxygen to produce nitrogen dioxide, but in the atmosphere, the production is more complex 3. one complex pathway to nitrogen dioxide requires the presence of VOCs and OH (a free radical) 4. the energy from the sunlight splits the nitrogen dioxide to oxygen and nitrogen monoxide 5. the free oxygen atoms in turn react with oxygen to form ozone

decane

10 carbon atoms`

ethane

2 carbon atoms

propane

3 carbon atoms

butane

4 carbon atoms

pentane

5 carbon atoms

hexane

6 carbon atoms

heptane

7 carbon atoms

troposphere

75% of the mass of the entire atmosphere

pure substances in the air

78% nitrogen, 21%oxygen, 1% other gases (argon, carbon dioxide, water)

octane

8 carbon atoms

nonane

9 carbon atoms

concentration in the air

the more toxic the pollutant, the lower its concentration must be set

chemical equation

the number and kind of atom on the left side of the arrow must equal those on the right

pollutants produced by cars

VOCs, NOx, particulate matter, CO

respiration

the process of metabolizing the foods we eat to produce carbon dioxide and water and to release the energy that powers other chemical reactions in our bodies

chemical reaction

the process whereby substance described as reactants are transformed into different substances called products. atoms are neither created nor destroyed during this process

CO

__ is measured in order to assess the efficiency of an automobile in most states in the US. this gas is measured in order to determine the degree of incomplete combustion

ozone

___ can affect lung function in humans and also damage crops

catalytic converters

___ have reduced the CO emissions fro cars

ozone

___ is a bad actor in the troposphere. even at low concentrations, it reduces lung function in healthy people who are exercising outdoor. it is a secondary pollutant

cardiovascular disease

___ is the primary hazard association with exposure to particulate matter

radon

___ is the second leading cause of lung cancer

ozone

___ varies with weather, season, and latitude because it depends on sun. therefore high levels of this are more likely to occur on a long, sunny day

VOCs; OH (hydroxyl radical); O3

___, ___, and ___ are involved in the conversion of NO to NO2

catalyst

a chemical substance that participates in a chemical reaction and influences its rate, without itself undergoing permanent change

organic compound

a compound that always contains carbon, almost always contains hydrogen, and may contain other elements such as oxygen or nitrogen

law of conservation of matter and mass

a law stating that in a chemical reaction, matter and mass are conserved

secondary pollutant

a pollutant produced from chemical reactions involving one or more other pollutants

higher

a toxic substance is hazardous when the concentration for it is at a ___ level than the standard for it

orange

air has become unhealthy for some groups (AQI color)

red or maroon

air is unhealthy for everyone to breath (AQI color)

green or yellow

air quality is good to moderate (AQI color)

not air pollutants

argon, nitrogen, water vapor

3

tri

VOCs

carbon containing compounds that pass easily into the vapor phase (evaporate easily)

CO2 and H2O (and heat)

complete combustion products

toxicity and exposure

what two factors are considered when determining the risk assessment for air pollutants?

10

deca

2

di

common names

do not follow a set of rules. these names cannot be figured out by simply looking at the chemical equation, you have to know them or look them up

temperature; pressure

equal volumes of gases contain the same number of atoms or molecules, as long as the samples are at the same ___ and ___

7

hepta

6

hexa

length of time

higher concentrations of a pollutant can be tolerated only briefly

crude oil

hydrocarbons we use today are primarily obtained from ___

CO2 H2O and CO

incomplete combustion products

aerosols

liquid and solid particles that remain suspended in the air rather than settling out. can contribute to pollution

1

mono

9

nona

8

octa

hydrocarbons

organic compounds comprised entirely of carbon and hydrogen. names are based on the number of carbon atoms. burn readily in oxygen to produce CO2 and H2O. primarily used as fuels

sunlight

ozone formation requires ___

causes of indoor air pollution

painting indoor walls, smoking, burning candles

5

penta

rate of breathing

people breath at a higher rate during physical activity. if the air quality is poor, reducing activity is one way to reduce exposure

air

some of its components are elemental substances: nitrogen and oxygen exist as diatomic molecules, while argon and helium exist as single, uncombined atoms

4

tetra

1;500

the air quality index is scaled from ___ to ___

ambient air

the air surrounding us, usually meaning the outside air

mixture

the air we breath is a ___

combustion

the chemical process of burning; the rapid reaction of fuel with oxygen to release energy in the form of heat and light. type of chemical reaction

shifting baseline

the idea that what people expect as "normal" on our planet has changed overtime, especially with regard to the ecosystem