Chem 100
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