CHEM chapter 2: Compounds and Air Quality

Which of the following options correctly describe hydrocarbons? Select all that apply.

- Gasoline and kerosene are mixtures of hydrocarbons. - Hydrocarbons burn readily in oxygen to produce CO2 and H2O. - Hydrocarbons are obtained from crude oil.

s - g - l - aq -

- solid - gas -liquid - aqueous

VOCs or _____ are a class of air pollutant that typically originates from _____.

volatile organic compounds; cars

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

Which two pollutants are responsible for the production of ozone in the troposphere?

- Nitrogen dioxide - Volatile organic compounds

Sulfur dioxide - Nitrogen dioxide and Ozone - Carbon monoxide - Particulate matter -

- released by volcanoes - produced during lightning strikes - may be produced by a wildfire, - includes dust and pollen

Hydrocarbons are primarily used as _____.

fuel

Which of the following is the primary source of atmospheric sulfur dioxide (SO2)?

coal-burning power plants

Which of the following are sources of particulate matter?

- Burning coal - Diesel engines - Wildfires

Which of the following options correctly DESCRIBE PARTICULATE MATTER? Select all that apply.

- 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.

Which of the following statements correctly describe the information gained from a balanced chemical equation? Select all that apply.

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

True or false: In order to balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid H2O a student adds a subscript of 2 to the oxygen in H2O. This is an acceptable method of balancing the above reaction.

FALSE, Subscripts of compounds involved in chemical reactions should never be changed because this changes the identity of the compound. Only coefficients should be added to balance chemical equations.

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

prefix

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

reaction, process, or change

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

remains unchanged

Balance the unbalanced equation given and match each substance to the correct coefficient as indicated. Al (s) + O2 (g) → Al2O3 (s)

4,3,2

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

μm

Ozone decomposes into oxygen and atomic oxygen. Which of the following statements correctly describe the balanced equation for this reaction? Select all that apply.

- 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.

sunny days rainy, windy weather

- higher O3 levels - lower O3 levels

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

Cardiovascular disease

In a combustion reaction, a hydrocarbon reacts with oxygen to produce carbon dioxide and water. Note that the 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

Which of the following is a natural source of both ozone and nitrogen oxides?

Lightning

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)

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

Which compound reacts with ozone, reducing the ozone concentrations along congested highways?

NO

A(n) ____ pollutant is produced from chemical reactions involving one or more other pollutants.

Secondary

True or false: Global greenhouse gas emissions can be thought of as an example of tragedy of the commons.

TRUE

True or false: After the completion of a chemical reaction the number of substances may change but the total mass of matter present remains constant.

TRUE, Matter is neither created nor destroyed in a chemical reaction, and this is reflected in the conservation of mass.

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 commons

Droplets that contain suspended solid and liquid particles are called _____.

aerosols

Organic compounds always contains the element _____.

carbon

Hydrocarbons are compounds that contain only _____ and _____.

carbon, hydrogen

Volatile organic compounds (VOCs) are ____ containing compounds that pass easily into the ____ phase

carbon, vapor

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

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

conservation of mass

Which of the following species are involved in the conversion of NO to NO2 in the atmosphere? Select all that apply.

- O3 (ozone) - OH⋅ (hydroxyl radical) - VOCs (volatile organic compounds

Which of the following options correctly describe ozone exposure and its effects?

- Ozone reacts with the rubber on car tires. - Ozone reduces lung function.

Which of the following options correctly DESCRIBE AIR pollutants? Select all that apply.

- Particulate matter is an example of an air pollutant. - Some air pollutants are hazardous at levels well below 1 ppm.

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.

Which of the following may increase the concentration of tropospheric ozone?

- Stagnant air - Sunny day

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 statements correctly describe a properly balanced chemical equation? Select all that apply.

- 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 formation and control of pollutants produced by cars?

- Volatile organic compounds are connected to the formation of nitrogen dioxide. - Catalytic converters have reduced the CO emissions from cars.

Is the chemical equation depicted in the illustration balanced? Why? (2P+2G+2G+2G=1P+3Gx2)

- Yes, there are the same number and type of atoms on each side of the chemical equation. - Yes the chemical equation is balanced.

What products may be formed when a hydrocarbon undergoes combustion? Select all that apply.

- heat - CO - CO2

The chemical formula CCl4 indicates that there is/are____, carbon atom(s) for every ___, chlorine atom(s)

1,4

Balance the unbalanced equation given and match each substance to the correct coefficient as indicated. C3H8 (g) + O2 (g) → CO2 (g) + H2O (g)

1,5,3,4

Identify the coefficients required to balance the chemical equation SO2 (g) + O2 (g) → SO3 (g)correctly.

2,1,2

Identify the coefficients required to balance the chemical equation C4H10 (g) + O2 (g) → CO2 (g) + H2O (g) correctly

2,13,8,10

The correct formula for the compound dichloride pentoxide is Cl _____ O _______. Enter your answer in the correct format. (You do not need to use any special formatting for subscripts as these are already included in the formula.)

2,5

Which of the following options correctly describe how to name a compound containing two nonmetals? Select all that apply.

- A Greek numerical prefix is always used when more than one atom is present to indicate the number of atoms of each element in the compound. - The second element is named with its root and the suffix -ide. - The name of the first element remains unchanged, except for the addition of a prefix where appropriate.

Which of the following options correctly describe the symbols used to write a balanced equation? Select all that apply.

- A pure liquid is indicated by the symbol (l). - The symbol (g) indicates a substance in the gas phase.

Which of the following options correctly describe aerosols?

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

Which of the following pollutants are generally produced by the majority of cars? Select all that apply.

- Carbon monoxide - Nitrogen oxides - Volatile organic compounds (VOCs)

Which of the following are CONSIDERED AIR POLLUTANTS? Select all that apply.

- Carbon monoxide - Ozone - Particulate matter - Nitrogen dioxide

Which of the following options correctly defines a secondary pollutant?

A secondary pollutant is a pollutant produced from one or more other pollutants.

What is a catalyst?

A substance that increases the rate of a reaction

A volatile substance readily undergoes a phase change from _____.

liquid to gas

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 oxide

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

number; type

A molecule that always contains carbon and may contain hydrogen, oxygen, and nitrogen is called a(n)___________ compound

organic

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

organic

Combustion is correctly described as _____.

the process in which a substance burns in oxygen

A species that passes easily from the liquid to the vapor phase is called a(n) _____ substance.

volatile

Place the chemical steps involved in ozone production in the correct order. Place the first step of the process at the top of the list and the last step at the bottom of the list.

- Nitrogen dioxide is exposed to sunlight. - Nitrogen monoxide and an oxygen atom are produced - An oxygen atom reacts with an oxygen molecule - Ozone is produced

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 or symbols - quantity, quantities, amounts, amount, proportions, or moles

When balancing a combustion reaction, which element should be balanced last?

oxygen