CHM1020 Ch. 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

A chemical equation must be balanced. This means that the same ________ and ________ of atoms must appear on both sides of the equation.

number and type

In the process of ________, the foods that we eat are metabolized to produce carbon dioxide, water, and energy.

respiration

Particulate matter with the designation PM10 includes particles with an average diameter of 10 ________ or less.

um

A species that passes easily from the liquid to the vapor phase is called a ________ substance.

volatile

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

Which of the following options correctly describe gases?

Gases are mostly empty space. Gas molecules are extremely small. Gas molecules are in constant random motion.

Which of the following are toxic gaseous pollutants that may be found in air?

O3 (ozone) SO2 (sulfur dioxide) CO (carbon monoxide)

Which of the following options correctly describes toxicity?

The toxicity of a substance may differ for different groups of people. Toxicity describes the intrinsic health hazard of a substance.

Match each indoor air pollutant correctly with it common source.

Tobacco smoke = Formaldehyde, benzene Paints and varnishes = VOCs Basements = Radon Ventilation systems = O3, NO2, SO2, CO

What term is used to describe the intrinsic health hazard of a substance?

Toxicity

The process of evaluating scientific data and making predictions in an organized manner about the probabilities of an outcome is called ________ assessment.

risk

A ________ pollutant is produced from chemical reactions involving one or more other pollutants.

secondary

Combustion is correctly described as ________.

the process in which a substance burns in oxygen

The typical amount of water vapor at the surface of the Earth is 10,000 - 40,000 ppm. What is this value as a percent?

1 - 4%

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.

If air is composed of 78% nitrogen this means that by volume air contains 78 parts nitrogen for every ________ parts of air.

100

Equal volumes of gases contain the same number of atoms or molecules, as long as the samples are at the same ________ and ________.

temperature and pressure

Which of the following options correctly describe particulate matter?

Dust is an example of particulate matter. Some particulate matter can pass into the bloodstream and cause heart disease. Particulate matter can originate from fires, car engines, or coal-burning plants.

A molecule is an independent structure composed of two or more ________ chemically bonded together.

atoms

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

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

1 ppm is ________ times smaller than 1%

10,000

Which of the following options describe the correct format used when writing the chemical formula of a substance?

A chemical formula is a symbolic way to represent the composition of a substance. The number of atoms of a particular element is indicated by a subscript.

Which of the following actions are permitted in balancing a chemical equation?

Adding coefficients to formulas of reactants and products Multiplying all coefficients by a common factor

Which of the following options correctly describe aerosols?

Aerosols can contribute to pollution. SO3 can combine with water to create sulfuric acid aerosols. Aerosols are liquid and solid particles that remain suspended in the air.

An inversion layer happens when a certain weather pattern traps cooler air near the surface of the earth with a warmer air mass above it. Why is this a problem?

Air pollution concentrates in the inversion layer

All of these pollutants can be detected by their odors except

CO

Which of the following are considered air pollutants?

Carbon monoxide Nitrogen dioxide Ozone Particulate matter

What ailment is the primary hazard associated with exposure to particulate matter?

Cardiovascular disease

Match each type of hydrocarbon combustion with the products formed.

Complete combustion = CO2 and H2O Incomplete combustion = CO2, H2O, and CO

Which of the following options correctly describe atoms?

Compounds contain two or more different types of atoms. An atom is the smallest unit of an element that can exist as a stable, independent entity. Atoms are extremely small.

If a compound is composed of nitrogen and hydrogen atoms in a respective one-to-three ratio, what is the correct chemical formula for this compound?

NH3

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 H20 = water CH4 = methane O3 = ozone

Which of the following are elements?

Na Cu O2

Which of the following statements correctly describe the information gained from a balanced chemical equation?

Often the physical states of reactants and products Identities of substances involved Relative quantities of substances involved

Give the correct chemical formula for sulfur tetrafluoride.

SF4

Which of the following statements correctly describes the sources and environmental effects of SO2 (sulfur dioxide)?

SO2 can lead to the formation of aerosols. SO2 can react with water to produce acid rain.

What is ambient air?

The air surrounding us, usually outside air

Organic compounds always contains the element ________.

carbon

Volatile Organic Compounds (VOCs) are ________-containing compounds that pass easily into the ________ phase.

carbon vapor

A ________ 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

A chemical equation that is properly balanced obeys the law of ________.

conservation of mass

The risks presented by pollutants are a function of toxicity and ________, the amount of a substance encountered.

exposure

A chemical equation is a statement using chemical ________ that expresses both the identities and the relative ________ of the reactants and products involved in a chemical or physical change

formulas quantity

Compounds that are made up of only hydrogen and carbon are called ________.

hydrocarbons

A volatile substance readily undergoes a phase change from ________.

liquid to gas

A molecule that always contains carbon and may contain hydrogen, oxygen, and nitrogen is called an ________ compound.

organic

Combustion is an example of a type of chemical ________, where reactants are transformed into products.

reaction

During a chemical reaction, the number of different substances may or may not change, but the total mass of matter present ________.

remains unchanged

Managing human consumption of natural resources so that these resources are not exhausted is called ________.

sustainability

Green chemistry is

the design of products and processes that reduce hazardous substances.

The concentration of water vapor in air ________.

varies widely according to location

The common name for the compound H2O is ________, while the compound NH3 is commonly known as ________.

water, ammonia.

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 actions are permitted in balancing a chemical equation?

Multiplying all coefficients by a common factor Adding coefficients to formulas of reactants and products

Atmospheric nitrogen reacts with atmospheric oxygen to form nitrogen monoxide. Which of the following is the correct balanced equation for this process?

N2 (g) + O2 (g) ----> 2NO (g)

Which of the following pollutants have short enough lifetimes that their concentration indoors is much lower than outdoors?

NO2 SO2 O3

For low concentrations, it is more convenient to use units of parts per ________ (ppm), instead of percent. This unit is of a concentration 10,000 times smaller than 1%.

million

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

When naming a compound composed of two nonmetals, the number of atoms of each element is indicated by a Greek numerical ________.

prefix

Which of the following options correctly describe the characteristics and behavior of argon, which is a component of air?

Argon is a typical component of air. Argon makes up less than 1% of air.

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.

Which of the following options correctly describe N2 (nitrogen gas)?

Nitrogen is the most abundant substance in air. Nitrogen is colorless and odorless.

Which of the following statements correctly describe radon?

Radon can be found in basements. Radon is radioactive. Radon is chemically unreactive.

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