CHEM ch 2
the correct formula for the compound dichlorine pentoxide is Cl-- O--.
2 ;5
which of the following is the correct molecular formula for dinitrogen pentoxide
N2O5
to improve air quality, different pieces of legislation have been enacted. match the piece of air quality legislation with it's intent
U.S. Clean Air Act- established air quality standards; focused on limiting exposure to hazardous substances Pollution Prevention Act- focused on prevention of formation of hazardous substances
different forms of the same element (such as O2 and O3) are called
allotropes
the smallest unit of an element that can exist as a stable independent entity is a/an
atom
"sick building syndrome" may result from
buildings with poor ventilation air filters that are not maintained
which of the following are sources of particulate matter
burning coal wildfires diesel engines
risk assessment involves
evaluating scientific data and making predictions about an outcome
air oxygen
is a mixture is a pure substance
a chemical equation must be balanced. this means that the same-- and --- must appear on both sides of the equation
number; type
match each set of weather conditions correctly to its effect on the concentration of ozone in our troposphere
sunny days = higher O3 levels Rainy/ windy weather = lower O3 levels
which of the following species are the two products of respiration
water; carbon dioxide
the typical amount of water vapor at the surface of the earth is 10,000- 40,000 ppm. that is this value as a percent?
1 - 4%
Place the gases that make up air in order of decreasing percent composition, starting with the most abundant gas at the top of the list.
1. Nitrogen 2. Oxygen 3. Argon
place the chemical steps involved in ozone production in the correct order
1. Nitrogen Dioxide is exposed to sunlight 2. Nitrogen Monoxide and an oxygen atom are produced 3. an oxygen atom reacts with an oxygen molecule 4. ozone is produced
which of the following pollutants have short enough lifetimes that their concentration indoors is much lower than outdoors
NO2 SO2 O3
Ozone decomposes into oxygen and atomic oxygen. which of the following statements correctly describe the balanced equation for this reaction?
O2 is a product of the reaction. There are 3 atoms of oxygen on the left side of the reaction and 3 atoms of oxygen on the product side of the equation.
VOCs or -- are a class of air pollutant that typically originates from --
Volatile Organic Compounds; cars
match each set of concentration units with its appropriate meaning
ppm= 1 part/1x10^6 parts ppb= 1 part/ 1x10^9 parts micro= 1x10^-6
match each form of matter with the correct description
pure substance- form of matter with a definite composition mixture- physical combination of two or more species
the species that passes easily from the liquid to the vapor phase is called a(n) -- substance
volatile
which of the following pollutants are generally produced by the majority of cars
volatile organic compounds (VOCs) carbon monoxide nitrogen oxides
if air is composed of 78 nitrogen this means that by volume air contains 78 parts nitrogen for every
100
The chemical formula CCl4 indicates that there is/are ____ carbon atom(s) for every ____ chlorine atom(s)
1; 4
Which of the following options correctly describe the symbols used to write a balanced equation?
The symbol (g) indicates a substance in the gas phase. A pure liquid is indicated by the symbol (l)
which of the following options correctly defines a secondary pollutant
a secondary pollutant is a pollutant produced from one or more other pollutants
which of the following options correctly describes atoms?
atoms are extremely small an atom is the smallest unit of an element that can exist as a stable, independent entity compounds contain two or more different types of atoms
which of the following is the primary source of atmospheric sulfur dioxide (SO2)?
coal-burning power plants
match each type of hydrocarbon combustion with the products formed.
complete combustion- CO2 and H2O incomplete combustion- CO2, H2O, and CO
A chemical ____ (e.g., CO2) represents the elementary composition of any pure substance
formula
hydrocarbons are primarily used as
fuel
even in very small concentrations ozone can affect -- function in humans. ozone also damages --, which are essential to human life
lung; crops
which of the following is the correct name for the compound NO2
nitrogen dioxide
a molecule that always contains carbon and may contain hydrogen oxygen and nitrogen is called a/an -- compound
organic
which noble gas is the second leading cause of lung cancer after cigarette smoke
radon
during a chemical reaction, the number of different substances may or may not change, but the total mass of matter present ---
remains unchanged
place the layers of Earth's atmosphere in the correct order, starting with the layer that is closest to the Earth at the top of the list
1. troposphere 2. stratosphere 3. mesosphere 4. thermosphere 5. exosphere
megacities contain -- people or more
10 million
balance the unbalanced equation given and match each substance to the correct coefficient as indicated. Al(s)+ O2(g)=Al2O3(s)
4Al + 3O2 = 2Al2O3 Al=4 O2=3 Al2O3=2
the Air Quality Index (AQI) describes the quality of air with a scale ranging from 1 to --. the number -- represents the national standard for the pollutant(s) being measured.
500;100
Which of the following options correctly describe elements and compounds?
A compound contains two or more different elements There are many more known compounds than elements Elements and compounds are pure substances
Which of the following statements correctly defines a molecule?
A molecule is an independent structure consisting of two or more atoms chemically bonded together
balance the unbalanced equation given and match each substance to the correct coefficient as indicated C3H8(g)+O2(g)=CO2(g)+H2O(g)
C3H8-1 O2-5 CO2-3 H2O-4
which one of the following gases is measured in order to assess the efficiency of an automobile in most states in the United States
CO ( carbon monoxide)
which of the following are toxic gaseous pollutants that may be found in the air
CO (carbon monoxide) O3 (ozone) SO2 (sulfur dioxide)
Which of the following actions are permitted in balancing a chemical equation.
Multiplying all coefficients by a common factor adding coefficients to formulas of reactants and products.
some compounds are so common that they are named using "common" or "trivial" names instead of systematic names. Match each of the following compounds with its correct name
NH3=ammonia H2O=water CH4=methane O3=ozone
which compound reacts with ozone, reducing the ozone concentrations along congested highways
NO
which of the following options correctly describe the characteristics and role of oxygen?
O2 is a necessary reactant in burning and rusting O2 is absorbed into our blood via the lungs Oxygen atoms are the most abundant atoms by mass in the human body
match each indoor air pollutant correctly with its common source
Tobacco smoke- formaldehyde, benzene paints and varnishes- VOCs Basements- radon ventilation systems- O3, NO2, SO2, CO
the term "shifting baseline" refers to
a change in what people expect as "normal"
droplets that contain suspended solid and liquid particles are called
aerosols
which of the following options correctly describe the characteristics and behavior of argon, which is a component of air?
argon makes up less than 1% of air argon is a typical component of air
a species capable of causing cancer is called a(n) -- compound
carcinogenic
a(n) -- is a substance that increases the rate of a reaction without being consumed. This type of substance is often used up but regenerated during the reaction
catalyst
which of the following options correctly describe the formation and control of pollutants produced by cars
catalytic converters have reduced the CO emissions from cars volatile organic compounds are connected to the formation of nitrogen dioxide
true or false: if an AQI value is reported at 93 this indicates that the sum of the pollutants present gives an AQI value of 93
false (the AQI value is set by the highest pollutant. other pollutants could be present lower AQI values)
A chemical equation is a statement using chemical __ that express both the identities and the relative __ of the reactants and products involved in a chemical or physical change
formulas; quantity
the set of principles used to design environmentally friendly chemical products and/or processes is called --- chemistry
green
what products may be formed when a hydrocarbon undergoes combustion
heat; CO, CO2
compounds that are made up of only hydrogen and carbon are called
hydrocarbons
in a combustion reaction, a hydrocarbon reacts with oxygen to produce carbon dioxide and water. Note that oxygen found in the reactants ends up in both products. In order to balance the chemical equation in the most efficient manner it is best to balance the oxygen atoms
last
sustainability is correctly defined as
meeting present needs without compromising the ability of future generations to do the same
match each prefix used for naming hydrocarbons with the number of carbon atoms it indicates
meth-= 1 eth-= 2 prop-= 3 but-= 4
for low concentrations, it is more convenient to use units of parts per --- (ppm) instead of percent. this unit if of a concentration 10,000 times smaller than 1%.
million
which of the following statements correctly describe different forms of matter?
mixtures can consist of any four phases of matter both mixtures and pure substances are forms of matter
output of carbon -- is used to measure the efficiency of an automobile. this gas is measured in order to determine the degree of -- combustion
monoxide; incomplete
which two pollutants are responsible for the production of ozone in the troposphere
nitrogen dioxide volatile organic compounds
which of the following are considered air pollutants
nitrogen dioxide ozone particulate matter carbon monoxide
Rank the pollutants from the most to the least toxic, based on the values given in the table. 1. CO - 4x10^4 2. O3- 2.35x10^2 3. PM2.5- 3.5x10^1
order from most to least toxic 3. PM2.5 2. O3 1. CO
when naming a compound composed of two nonmetals, the number of atoms of each element is indicated by a Green numerical--
prefix
a chemical reaction is a process whereby substances called-- are transformed into different substances called --.
reactants; products
the process of evaluating scientific data and making predictions in an organized manner about the probabilities of an outcome is called --- assessment
risk
which of the following options correctly describe particulate matter?
some particulate matter can pass into the bloodstream and cause heart disease dust is an example of particulate matter particulate matter can originate from fires, car engines, or coal-burning plants
match each air pollutant with its natural source
sulfur dioxide- released by volcanoes nitrogen dioxide and ozone- produced during lightning strikes carbon monoxide- may be produced by a wildfire particulate matter- includes dust and pollen
equal volumes of gases contain the same number of atoms or molecules, as long as the samples are at the same -- and --
temperature; pressure
what is ambient air
the air surrounding us, usually outside air
which of the following statements correctly describe a properly balanced chemical equation?
the physical states of the reactants may be different than the physical states of the products the total number of atoms of each element must be the same in the reactants and products
which of the following options correctly describe the troposphere
the troposphere is the region 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
what term is used to describe the intrinsic health hazard of a substance
toxicity
which of the following options correctly describe toxicity
toxicity describes the intrinsic health hazard of a substance the toxicity of a substance may differ for different groups of people
what term is used to describe a situation where a resource is no particular group's responsibility but if it is destroyed or overused this has consequences for a large number of people
tragedy of the commons
which of the following options correctly describe aerosols
aerosols are liquid and solid particles that remain suspended in the air SO3 can combine with water to create sulfuric acid aerosols aerosols can contribute to pollen
match each air pollutant to the correct description
sulfur dioxide- sharp, unpleasant odor; produced by burning coal carbon monoxide- colorless, tasteless, and odorless, the "silent killer" ozone- sharp odor; a pollutant in the immediate atmosphere but essential at high altitudes nitrogen dioxide- characteristic brown color; emitted from car engines particulate matter- classified by size rather than composition
which of the following gases is measured in order to assess the efficiency of an automobile in most states in the united states
CO
rank the three pollutants listed in the table below in order of decreasing toxicity, based on the U.S. National Ambient Air Quality Standard for a 1-hour exposure period. Start with the most toxic pollutant at the top of the list CO=35 NO2=0.100 SO2=0.075
1. SO2 2. NO2 3. CO
the concentration of water vapor in air
varies widely according to location
which of the following questions correctly describe the factors that affect air quality
weather patterns have an affect on air quality the number of people living in a region affects air quality
greek numerical prefixes
1- mono 2-di 3-tri 4- tetra 5-penta 6-hexa 7-hepta 8-octa
The risks presented by pollutants are a function of toxicity and --,the amount of a substance encountered
exposure
gas molecules are in constant random motion and are extremely-- under normal atmospheric conditions. if the gas molecules in a sample of air were condensed their actual volume would be very--
far apart; small