Chem 100

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Which shows the balanced equation for the reaction of nitrogen ( ), as it is normally found in our atmosphere, with oxygen ( ), as it is normally found in our atmosphere, to form nitrogen dioxide?

(balls) two + two+ two = three

The numbers 1 through 4 are used to identify four different elements on the periodic table. Which element is expected to have 2+ charge when it forms an ion?

1

Choose the proper coefficients for each substance to balance this equation. ___ C2H4(g) + ___ O2(g) → ___ CO2(g) + ___ H2O(g)

1,3,2,2

This is the Lewis structure for acetic acid. The bond angles are not drawn to scale. (H-C-O, lewis structure) Based on the electronic configuration shown in the Lewis structure, predict the O C O bond angle, in degrees.

120°

Calculate the mass of CO2 produced by the combustion of a tank of gasoline. Assume the mass of gasoline is 46.0 kg and that gasoline is pure octane (C8H18).

142 kg

Balance this equation P4 + Cl2 → PCl5 with the smallest whole number coefficients. Choose the answer that is the sum of the coefficients. (Do not forget coefficients of "one.")

15

Which of the following would be described as "fine particles?"

2.5 μm diameter soot

Which is the correct balanced equation for the complete combustion of ethane in excess oxygen?

2C2H6 + 7 O2 → 4 CO2 + 6 H2O

Which component of the air makes up approximately 100 times more of an exhaled breath than of an inhaled breath?

CO2

Although carbon dioxide is the primary compound discussed with respect to global warming; of the common atmospheric components the global warming potential (GWP) of a carbon dioxide molecule is very low. Which statement best explains this pair of facts?

CO2 exists in relatively high concentrations

What is the chemical formula for carbon disulfide?

CS2

Which contributes to the ozone hole?

Chlorofluorocarbons (CFCs)

How many protons, neutrons, and electrons are there in a neutral atom of 19/9 F?

D

The most abundant greenhouse gas in Earth's atmosphere is

H2O vapor

Which is the balanced chemical equation showing hydrogen peroxide (H2O2) decomposing into hydrogen (H2) and oxygen (O2)?

H2O2 → H2 + O2

Which is the correct Lewis structure?

H=CL (8 dots around CL)

What is the effect of the absorption of infrared energy on matter?

It increases the vibration of chemical bonds

Which one of the following compounds is considered to be an ionic compound?

LiF

Predict the shape of nitrous oxide, N2O (atomic order N — N — O)

Linear

What is the primary component of an exhaled breath?

N2

Which substance is an element?

N2

The chemical formula for nitrogen monoxide is

NO

Which is not a pure substance?

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

Which chemical components are given off in car exhaust?

all choices are correct

Decreased stratospheric ozone concentrations may lead to

all of these choices are correct

Which is correct?

all of these choices are correct

Which of the following are ways that aerosols may affect climate?

all of these choices are correct

In their fifth and most recent report published in 2014, the vast majority of scientists agreed on several key points. Which of the following is NOT one of those points?

all of these choices were mentioned as key points

Free radicals are

all of these correctly describe free radicals

The greenhouse effect refers to the process by which

atmospheric gases trap and return infrared radiation radiated by Earth

The structure of ozone most closely resembles a

bent molecule with the same length of chemical bonds

Light behaves like

both a particle and a wave

Scientists have correlated average global temperature with atmospheric carbon dioxide levels for the last 160,000 years using ice cores from Antarctica. How is the carbon dioxide level determined?

by measuring the CO2 concentration in trapped air bubbles in the ice layers

Which pollutant are you more likely to encounter in dangerous concentrations indoors rather than outdoors?

carbon monoxide

Which explanation accounts for the fact that, on average, cloudy nights are warmer than clear nights?

clouds are composed of water vapor and H2O is a strong greenhouse gas

Currently, the primary source of sulfur dioxide emissions into the atmosphere is

coal burning power plants

A substance that can be broken down into two or more simpler substances by chemical methods is called a(n)

compound

What is the greatest source of indoor air pollution in developing countries?

cookstoves

A recent set of advertisements has a picture of an aluminum can with an aluminum-frame bicycle, along with a hypothetical quote from the can that reads: "I want to be a bike. Recycle me." The analysis of the life cycle of an item starting with its raw materials and ending with the used item becoming the raw material for new products is called

cradle-to-cradle

What type of material is defined as having a well-ordered atomic structure?

crystalline

Identify the single most effective strategy to reduce carbon dioxide emissions

develop alternate energy sources that do not rely on fossil fuels

P2O5 is the chemical formula for

diphosphorus pentoxide

Wavelength is the

distance between successive peaks in a wave

What term is defined as the flow of electrons from one location to another?

electricity

Oxidation and reduction of atoms involves a change in the number of ___________ in the atom.

electrons

Which process plays the most important role in the greenhouse effect?

energy radiated by the earth is absorbed by the atmosphere

What are the three pillars of sustainability?

environmental, social, economic

On a Periodic Table, the columns of elements with similar properties are

groups

Single bonds, double bonds, and triple bonds

have 2, 4 and 6 shared electrons, respectively

The "ozone layer" is found

in the stratosphere

Chlorofluorocarbons rise to the stratosphere and

interact with UV energy to produce free radicals that destroy ozone

Land use changes have a big impact on global warming because of their effect on albedo. Albedo

is the ratio of electromagnetic radiation reflected by a surface to the amount of radiation hitting that surface

The most numerous of the elements are the

metals

Based on its name, which carbon compound contains the fewest carbon atoms?

methane

A(n) ________ is a fixed number of atoms held together by chemical bonds in a certain spatial arrangement.

molecule

The carbon cycle refers to the

movement of carbon through living organisms, the atmosphere, the sea, and the earth

In order to halt increases in the amounts of these gases in the Earth's atmosphere, global greenhouse gas emissions must be decreased by 9 billion tons. Which of these would not provide that much relief in global greenhouse gas emissions?

none of these choices would provide the needed 9 billion tons

Ozone is a secondary pollutant. A secondary pollutant is

not produced directly but as the product of the interaction of two or more pollutants.

The atomic number is the

number of protons in a nucleus

In reference to waves, frequency is the

number of waves passing a fixed point in one second

Which characteristics pertain to the problem of global warming? i. Possible consequences include altered climate and increased sea level. ii. Heat energy radiated by the earth is captured by atmospheric molecules. iii. Increased skin cancer incidence and damage to radiation sensitive species has been observed. iv. The concentration of stratospheric ozone is declining.

one and two only

Which diagram(s) best represent(s) only molecules?

one and two only

The two chemical bonds and geometry of water are best represented by

one circle middle(top) & two circles hanging (bottom)

Which square(s) contain(s) only one or more compounds?

one only

Methane is approximately 23 times more powerful than carbon dioxide as a greenhouse gas. Which are significant sources of methane emissions? i. The digestive systems of ruminants (cows, sheep, etc.) ii. Automobile exhaust iii. Rice cultivation iv. Decaying wetland vegetation

one, three, and four only

In order to make useful predictions, which factors must be accounted for by climatic models? i. Aerosol Emissions ii. Land Use iii. Solar Irradiance

one, two, and three only

Identify possible consequences of global warming. i. A rise in sea level ii. An increase in average relative humidity iii. An increase in forest growth in the Northern Hemisphere iv. A weakening of ocean currents

one, two, three and four

In order to make useful predictions, which factors must be accounted for by climatic models? i. Cooling effect of atmospheric aerosols ii. Smoke, haze, and cloud cover iii. Change in land use iv. Combustion of fossil fuels

one, two, three, and four

The Industrial Revolution is a key point in the Earth's atmospheric history because

prior to that time large deposits of petroleum and coal were not being used as energy sources

The nucleus of an atom contains

protons and neutrons only

Which air pollutant is the second-leading cause of lung cancer worldwide, behind tobacco smoke?

radon

When only one pair of shared electrons is involved in a covalent bond, the linkage is called a ____ bond

single

Which is not a mixture?

sodium chloride

Green chemistry is

the design of products and processes that reduce hazardous substances

In metropolitan areas, the concentration of ozone in the atmosphere drops at night. Why?

the formation of ozone requires sunlight

What distinguishes the atoms of one element from another?

the number of protons

When assessing the risk of an air pollutant, which does not play a role in considering someone's exposure to the pollutant?

the toxicity of the pollutant

Why are HFCs inappropriate for long-term replacement of CFCs?

they absorb infrared radiation

In the periodic table, which elements typically have similar properties?

those in the same columns

Which squares contain mixtures?

three & four only

Which is one of the Lewis structures for ozone?

three o's (18 dots, except middle and left middle)

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

toxicity and exposure

Which square(s) contain(s) only an element?

two only

DNA, the genetic material of living organisms, is damaged by light in the

ultraviolet region, especially below a wavelength of 320 nm

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

Ozone in our atmosphere is important because it

absorbs some UV radiation

Which two gases make up more than 95 percent of an inhaled breath?

O2 and N2

Which one of the following compounds is considered to be a molecular compound?

PCl3

Arrange these types of radiation in order of increasing energy per photon: gamma rays, infrared radiation, radio waves, visible light, UV (ultra violet)

Radio waves < infrared radiation < visible light < UV < gamma rays

Scientists believe they know the average global temperature over the last 160,000 years. Which property of the ice core samples from Antarctica provides this information?

The 1H/2H ratio

How do mineral nanoparticles in sunscreens protect from UV radiation?

The particles absorb incoming UV light

Determine the shape or geometry of PH3. (Hint: Use the Periodic Table to arrive at the electron configuration for phosphorous.)

Trigonal pyramidal

Which region of the ultraviolet spectrum is absorbed least by the atmosphere?

UV-A

Which of the following is most biologically damaging type of radiation?

UV-C

Which statement is correct?

UV-C is the most energetic of the three forms of UV light

Increasing wavelength of light goes in this order

Ultraviolet > visible > infrared

Which country has the highest per capita emission of carbon dioxide?

United States

Which compounds are used in mineral-based sunscreens?

ZnO and TiO2

Which one of these materials is most likely to conduct heat?

a titanium rod


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