Chem quizzes and tests
which of these are correct? -All of these are correct -there is a dynamic steady state of ozone in the stratosphere -UV radiation will dissociate ozone into an oxygen atom and an oxygen molecule -ozone forms by combining an oxygen atom with an oxygen molecule
-all of these choices are correct
assuming that the burette was originally filled to the "0 mL" line at the top, what volume of liquid has been added to the titration at this point in the experiment?(3 marks above the 20 mL line)
17.0 mL
Provide the proper coefficients (including 1's) required to balance this reaction:
1;3;2 (1N2+3H2-->2NH3
what is the answer to the following mathematical operation? 1.42+10.3x 2.854
30.8
Calculate the molar mass of N2O. In your answer, use 1 decimal place.
44.0 g/mol
which of these represents the best lewis structure for acetylene (C2H2)?
A: H-C=(three lines)C-H
which of the following is the chemical symbol for silver?
Ag
The ozone hole is most prominent on the earth over
Antarctica
HFCs may be used to replace CFCs. Which compound is a HFC?
CF3CH2F
which component of air makes up approximately 100 times more of an exhaled breath than of an inhaled breath
CO2
Which lewis structure for formaldehyde (CH2O) is correct
D H. . .. C : : O . . H
why are HFCs environmentally superior to the currently used HCFCs?
HFCs do not contain chlorine
which square(s) contain(s) only one or more compounds
I only ( both compound pictured are exactly alike and has a dark center molecule with 2 light molecules attached. )
which substance is an element?
N2
which component of the air is an element
O2
which correctly pairs and indoor pollutant with its source?
O3 and electrical arching
which of the following is most biologically damaging type of radiation?
UV-C
which symbols represent only elements that are metals?
X and Z ( the left side of the table)
which one of the following is an example of a homogeneous mixture?
a glass of pulp free lemonade
which color in the rainbow has the shortest wavelength?
blue
light behaves like
both a particle and a wave
which process plays the most important role in the greenhouse effect?
energy radiated by the earth is absorbed by the atmosphere
the "ozone layer" is found
in the stratosphere
Describe the shape of a CO2 molecule.
linear
which is not a mixture?
sodium chloride
Calculate the wavelength of a photon of electromagnetic radiation with a frequency of 1 MHz.
300 m
rank these substances in order of their abundance in the air you breathe.
(most abundant)O3<CO2<Ar<O2<N2 (least abundant)
For similar light intensity, compact fluorescent bulbs use about 25% of the energy of incandescent bulbs. Let's say you replaced a bulb of 60 W with a fluorescent bulb and that your utility charges $0.15/kW-hour. How many dollars would you save in electricity in the 10,000−hour lifetime of the bulb?
$68
an oil refinery separates crude oil into its components by distillation. some components are altered by "cracking" and "reforming" to be made into more useful mixtures. label each of the outlets on the refinery tower below with the products that are produced
(top to bottom) -refinery gases -gasoline -jet fuel -diesel -refinery gases and gasoline -gasoline, jet fuel, and diesel -industrial fuel lubricants -asphalt
sort the elements below by the charge that they will bear as ions. you may want to refer to a periodic table for assistance.
+2: Sr; Ba; Zn +1: Cs; K; Ag -1: Cl -2: S
classify each of the following diatomic species as ionic, polar covalent or nonpolar covalent.
- ionic: NaCl; KF; LiBr; CaO -Polar covalent: HBr; HCI -nonpolar covalent: Br2; O2; N2
Place the events of the history of ozone depletion in chronological order.
-1930s- Chlorofluorocarbons (CFCs) are invented and used as propellants and refrigerants by people worldwide. -1974-F. Sherwood Rowland, Mario Molina and Paul Cruzen discover that CFCs are a major cause of stratospheric ozone depletion. -1977-The United Nations meets and adopts the World Plan of Action on the Ozone Layer. -1978-The US and Canada ban the use of CFCs in spray cans. -1987-The Montreal Protocol on Substances That Deplete the Ozone Layer is signed and ratified by countries worldwide. -1990- present-Production and use of CFCs and other ozone depleting agents dramatically decreases.
the following molecules contain only single bonds NH3(g)+3F2(g)->NF3(g)+3 HF(g) the bond energies are: N-H 391 kJ/mol; F-F 158 kJ/mol; N-F 272 kJ/mol; H-F 566 kJ/mol. Which is the heat evolved or absorbed per mole of NH3 that reacts with F2?
-867 kJ/mol
the sun is the most powerful, reliable energy source available on earth. As photovoltaic cells become more efficient, solar power is becoming a more realistic option for supplying our energy needs. fill in the blanks in the sentences below about photovoltaic cells.
-Photovoltaic cells (PVs) convert light energy into electrical energy. -PVs are made from semiconductors. Two different types are layered - n-type semiconductors have extra electrons and p-type semiconductors need more electrons. -Dopants such as gallium or arsenic are added to allow electrons to flow through the silicon semiconductor. -When a photon with enough energy hits the PV, an "extra" electron is "knocked" from one layer into a "hole" in the other. The movement of electrons is an electrical current.
in these diagrams, different atoms are represented by different colors. classify each sample according to the labels below
-Pure element- 1. (the 5 sets of green figure 8's) 2. (the 5 sets of all blue groups of 3) 3. (the 8 single purple dots) -pure compound- 1. (the purple and orange; 2 dots. each with one purple and one orange). 2. (the triple set with 2 blue and one yellow each) -mixture of an element and a compound- 1. (sets containing 2 dots each. some sets are 2 purple, some are 1 purple and one yellow -mixture of 2 elements-1. (orange and green single dots) 2. (5 sets of dots. sets contain 2 dots. 2 yellow dot sets, 3 purple dot sets -mixture of 2 compounds- 1. (2 dot sets, green/purple & yellow/ blue) 2. (5 triple sets, some 2 green/1 orange and some 2 orange/ 1 green)
the warming of a car in the sun is an excellent analogy for the greenhouse effect of our atmosphere. complete the analogy with the words and phrases then place the sentences in order.
-When sunlight hits a car, its windows absorb some radiation, such as UV-B. In the atmosphere, all of the UV-C and some of the UV-B radiation is absorbed by reactions of oxygen and ozone in the stratosphere. -The car windows allow visible light and infrared radiation to pass into the car. Similarly, our atmosphere allows higher energy infrared radiation and visible light to pass through. -The car's interior, like the Earth's rocks and soil, absorbs visible light and higher energy infrared radiation then emits lower energy infrared radiation back out. -The car windows, like the greenhouse gases of our atmosphere, trap the lower energy infrared radiation and makes the interior warmer than the outside.
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 these points? -if the rate of greenhouse gas emissions is not curtailed, our water resources, food supply, and even our health will suffer -human activities (primarily the combustion of fossil fuels and deforestation) are responsible for much of the recent warming -the earth is getting warmer -all of these choices were mentioned as key points
-all of these choices were mentioned as key points
fill in the table with the properties of the different types of nuclear radiation.
-alpha-4He2 or a; 2 protons & 2 neutrons; 2+; mass number -4, atomic number 2 -beta- 0e-1 or b; 1 electron; 1-; mass number unchanged atomic number +1 -gamma- 0y0 or y; a photon; 0; mass number unchanged, atomic number unchanged
most of the electricity in the U.S. is produced by converting the energy in fossil fuels to electricity. Fill in the types of equipment required for this transformation
-chemical potential energy (fuel); burner -kinetic energy; turbine -mechanical energy; generator
vibrations of some molecules will absorb infrared radiation while others will not. Do the following vibrations absorb?
-nitrogen: no -dichlorodifluoro-methane: yes -carbon dioxie: no
generating electricity has its risks, no matter what type of fuel is used. identify which consequences are associated with generating electricity in a coal-fired power plant and which accompany nuclear power. some risks may belong in both categories
-nuclear; safety of mine workers; generation of greenhouse gasses; generation of high-level nuclear waste; mine tailings and mill waste -coal- safety of mine workers; generation of greenhouse gasses; generation of air pollutants; release of mercury, uranium and thorium; generation of ash
which of the following are methods of making sea water appropriate for drinking? (more than one choice may be appropriate.)
-osmosis -reverse osmosis -distillation -flocculation
match the chemical formula with the correct name for each alkane.
-pentane; C5H12 -heptane; C7H16 -ethane; C2H6 -hexane; C6H14
Give the number of protons, neutrons, and electrons in a neutral atom represented by 69Ga31 .
-protons: 31 -neutrons: 38 -electrons:31
label the reactants, products, and energy changes in the reaction coordinate diagram below. Define the reaction as endothermic or exothermic
-reactants -overall energy change -activation energy -products -Exothermic (the red line begins in the middle of energy scale and rises to the very top before falling to the bottom)
Give the chemical name for H2SO4. Give the chemical name for the aqueous solution that forms when the gas HBr dissolves in water.
-sulfuric acid -hydrobromic acid
predict the molecular shape for each of these compounds. remember to consider all of the outer electrons before you make your choice.
-tetrahedral: methane -Trigonal pyramidal: ammonia -trigonal planar: sulfur trioxide -bent: water; ozone
which one is the lewis structures for ozone (view answer in half screen)
.. .. .. O : : O : O : .. ..
Write 3.26 × 10−2 g as a "regular" number; that is, without scientific notation.
.0326
the EPA limit for CO is 9ppm. express this number as a percentage
0.0009 percent
hard water in parts of the midwest may have a calcium ion concentration as high as 400 ppm. what is this calcium ion concentration when expressed as a percentage?
0.04 percent
Assume that coal can be represented by the chemical formula C135H96O9NS. If 7.0 tons of coal is burned, what mass of nitrogen is found in the NO produced by this process?
0.051 tons nitrogen
if the lead concentration in water is 1 ppm, then we should be able to recover 1 mg of lead from - L of water.
1
Silicon used for solar panels is found to be 99.99% pure. What is the concentration of impurities in ppb?
1,000 ppb
they hydronium ion concentration in a solution with pH 10 is - than the hydronium ion concentration in a solution with pH 13
1,000 times greater
label the diagram below with the different types of electromagnetic radiation in the EM spectrum
1. Gamma rays (10^-12) 2. X-rays (10^-9) 3. Ultraviolet (UV) (10^-8) 4. Visible (10^-7) 5. Infrared (IR) (10^-5) 6. Microwave (10^-2) 7. Radio (10^1.5)
ozone is a dangerous secondary pollutant in our atmosphere. fill in the blanks and then rearrange the sentences to describe the formation of ozone
1. Nitrogen monoxide is produced when nitrogen & oxygen are exposed to high heat. 2.At high concentrations, nitrogen monoxide will directly react with oxygen to produce nitrogen dioxide, but in the atmosphere, its production is more complex. 3. One complex pathway to nitrogen dioxide requires the presence of VOCs and ·OH (a free radical). 4. The energy from sunlight splits the nitrogen dioxide to oxygen and nitrogen monoxide. 5. The free oxygen atoms in turn react with oxygen to form ozone.
Express 105 m in terms of nm.
1.05; 11 (1.05x10^11 nm)
calculate the mass of 25,000 molecules of nitrogen gas. (1 mole=6.2x10^23 molecules)
1.16x10^-18 g
Although it is not usually used, Einstein's equation, E = mc2 applies to chemical reactions as well as nuclear reactions. A combustion reaction released 95 kJ when one gram of a reactant was burned. How much of this mass was lost in the process? 1 joule = 1 kilogram-meter2/second2
1.1x10^-9 g
How many atoms are contained in 3.1 g of carbon? Round your answer to 2 significant figures.
1.6 x 10^23 atoms
there are approximately 2x10^22 molecules and atoms in each breath we take and the concentration of CO in the air is approximately 9 parts per million. approximately how many CO molecules are in each breath we take?
1.8 x 10^17
these are approximately 2x10^22 molecules and atoms in each breath we take and the concentration of CO in the air is approximately 9 parts per million, approximately how many CO molecules are in each breath we take
1.8x 10^17
To burn 1 molecule of C7H16 to form CO2 and H2O (complete combustion), how many molecules of O2 are required?
11 molecules
To draw a Lewis structure, first add the number of outer (valence) electrons contributed by each atom to obtain the total number of outer electrons. What is this value for a molecule of H2CCH2?
12 total valence electrons
what percentage of a radioactive isotope would remain after three half-lives
12.5 percent
If a 5.00−minute shower requires 85.0 L of water, how much water would you save if you shortened your shower by 45.0 seconds?
12.7 L
this is the lewis structure for acetic acid. the bond angles are not drawn to scale. Based on the electronic configuration shown in the lewis structure, predict the O-C-O bond angle, in degrees
120 degrees
The nuclear fission of U−235 can occur by different pathways. If 3 neutrons and 92Kr36 are produced, what is the other fission product?
141Ba56
balance this equation P4+Cl2-->PCl5 with the smallest whole number coefficients. choose the answer that is the sum of the coefficients.
15
if the average temperature of earth is currently 15.0 degree C, what does the NOAA model (in the line graph) predict for the average global temperature in 2080?
17.4 degree C
To draw a Lewis structure, first add the number of outer (valence) electrons contributed by each atom to obtain the total number of outer electrons. What is this value for a molecule of SO2?
18 outer electrons
label the mass number and atomic number for the symbol of gold below. how many protons and neutrons are in the nucleus of this isotope of gold?
197- mass number 79- atomic number number of nutrons- 118 number of protons- 79
according to the graph below, the net U.S. import of petroleum drastically decreased during the years
1977 to 1982
what is the concentration of hydroxide ions in an aqueous solution containing [H+]=1x10^-5M
1x10^-9M
What is the mass of one atom of carbon (C)? Report your answer to 2 significant figures.
2.0 × 10^-23g
if 1.8x10^14 J is released in a nuclear reaction, how much matter was lost
2.0x10^-3kg
how many atoms are present in 0.375 mol of palladium (Pd) atoms?
2.26x10^23
a 4-L sample of water contains 80 mg of lead. what is the lead concentration, in parts per billion (ppb)?
20
Calculate the volume of air in liters that you might inhale (and exhale) in 1.0 hour. Assume that each breath has a volume of 0.31 liters, and that you are breathing 11 times a minute.
204.6
the energy equivalent of a certain cheeseburger is approximately 525 Cal. since 1 Cal is 4.184 kJ this corresponds to
2200 kJ.
when fission of uranium-235 is initiated by a neutron it can result in many different products. fill in the correct isotope to complete each reaction
235U92+1n0-> 144Cs55+ 90Rb37+2 1n0 235U92+ 1n0--> 92Kr36 + 141Ba56 +3 1n0 235U92+ 1n0--> 89Se34+ 144Ce58 + 3 1n0 235U92+ 1n0--> 90Sr38+ 143Xe54 +3 1n0
In Chapter 6, neutrons were given by the following symbol: 1n0. An alpha particle (a helium atom) is designated as 4He2 or α.The collision of 239Pu94 with an alpha particle generates a new isotope and one neutron. What is the new isotope that is produced in this nuclear reaction?
242Cm96
In Chapter 6, neutrons were given by the following symbol: 1n0. An alpha particle (a helium atom) is designated as 4He2 or α The collision of 242Cf98 with an alpha particle generates a new isotope and one neutron. What is the new isotope that is produced in this nuclear reaction?
245Fm100
After 2 half-lives have passed, what % of the original radioactive isotope remains?
25%
if you have 200.0 g of radioisotope with a half-life of 5 days, how much isotope would remain after 15 days?
25.0 g
one of the lightest smartphones on the market today weighs 113 g. to protect your phone, you may want to use a screen protector, which weighs 27.2 g, and a heavy duty phone case, which weighs 114 g. what is the total weight of the phone, screen protector, and case
254 g
In Chapter 6, neutrons were given by the following symbol: 1n0. Here are some other types of particles that are involved in nuclear reactions: Protons: 1p1 Alpha particle (a helium atom): 4He2 or α Beta particle (an electron): 0β−1 or β Gamma radiation (a high-energy photon): 0γ0 or γ Positron particle (same mass as an electron, but carries a positive charge): 0β1 or β+ What nuclide will result from positron emission by the 28Si14 nucleus?
28Al13
how many bromide ions can combine with one ion of aluminum to form an ionic compound
3
how many bromide ions can combine with one ion of aluminum to form an ionic compound?
3
numbers 1-4 are used to identify four different elements. based on periodic table trends, which number identifies the element that is expected to have the greatest tendency to attract a shared pair of electrons?
3
a sample of silicon rejected for use in an electronic circuit has an impurity of boron at a level of 3 parts per trillion. what is the fraction of boron atoms in the silicon sample as written in scientific notation
3 X 10^-12
although coal is a complex mixture of substances, its elemental composition can be approximated by the formula C135H96O9NS. using this formula, predict the amount of CO2 released from the combustion of 1.00x10^6 metric tons of coal (about the annual average for a coal-fired power plant). 1 metric ton=1x10^3 kg.
3.11x10^9kg
A coal-burning power plant generates electrical power at a rate of 350 megawatts (MW), or 3.50 ×10^8 J/s. The plant has an overall efficiency of 36% for the conversion of heat to electricity. Given this efficiency, how much heat energy in joules is produced in one year of operation??
3.1x10^16 J
WUKF FM transmits at 93.5 MHz. What is the wavelength of the electromagnetic radiation that carries the station's signal?
3.21 m
Nail polish remover containing acetone was spilled in a room 6.6 m × 5.2 m × 2.9 m.Measurements indicated that 3,600 mg of acetone evaporated. Calculate the acetone concentration in micrograms per cubic meter. --X 10^-- μg/m3 (Enter your answer in scientific notation.)
3.6X10^4μg/m3
the recommended daily requirement of calcium is 1,000 mg. tap water in a midwestern city contains approximately 150 mg Ca/L. a person living in the city who drinks two liters of water in one day would receive - percent of his/her RDA of calcium
30
To produce the same energy, it takes 1.6 times more coal (by volume) than oil. How many gallons of oil will give you the same amount of energy as 350 pounds of coal. Assume that 1 pound of coal has a volume of 0.14 gallons.
31 gallons
the pH of lemon juice is approximately 2.40. at this pH, the hydronium ion concentration is closest to which concentration?
4.0x10^-3 M
LP gas (liquid propane, C3H8) is the fuel used in gas grills as well as a main source of heat energy for many rural residences. What is the mass of 5.83 x 10^17 molecules of liquid propane?
4.27 x 10^-5 g
LP gas (liquid propane, C3H8) is the fuel used in gas grills as well as a main source of heat energy for many rural residences. what is the mass of 5.83 x 10^17 molecules of liquid propane?
4.27 x 10^-5 g
as of 2007, what is the maximum efficiency of a multijunction solar cell
40 percent
what, approximately, is the highest concentration of CO2 measured in the Earth's atmosphere in modern times
400 ppm
consider the following equation the describes the complete combustion of propane, C3H8.
4040 kJ/mol
choose the best reading of the volume of the liquid contained in the beaker and the temperature measured by the thermometer. make sure your answers have a reasonable number of decimal points.
41 mL; 57.0 degree C
a calorie is defined as exactly 4.184 J. therefore 1.000 Cal is exactly
4184 J.
most aquatic life in lakes cannot survive in water with a pH less than
5
Give the number of outer (valence) electrons for an atom of phosphorus.
5 outer electrons
different ways of expressing concentrations work best for different things. concentrations of pollutants are often expressed in parts per million because they are very small, even though their effects can be large. convert the parts per million values into percentages
5-0.0005% 50- 0.005% 500-0.05% 5000-0.5% 50000-5%
the pH of rain water falling through an unpolluted atmosphere is closest to
5.4
From the data in the table, what dose of radiation (in rem) marks the start of changes likely to occur in skin cells?
50 rems
The heat of combustion of ethane, C2H6, is 1560 kJ/mol. What is the heat of combustion of ethane, in kJ per gram?
51.9 kJ/g
how many protons are in an atom of carbon
6
the half-life of carbon-14 is 5,730 years. if you started with 100.0 g of carbon-14, how much would remain after 4 half-lives?
6.25 g
The quantity 0.0000064 g expressed in scientific notation
6.4 X 10^-6 g
One year, a herd of cattle released 8.6 metric tons of CH4 (methane) into the atmosphere. How many metric tons of carbon did this methane contain?
6.5 metric tons C
how many joules are required to heat 2.0 L of water from 20 degrees C to its boiling point of 100 degrees C? the specific heat of water is 4.18 J/g. degree C and the density of water is 1g/mL
6.7x10^5J
A single serving bag of snack chips contains 69.0 Cal. Assuming that all of the energy from eating these chips goes toward keeping your heart beating, how many hours can these chips sustain a heartbeat of 79 beats per minute? Note: 1 Cal = 1 kcal = 4.184 kJ and each heartbeat requires approximately 1 J of energy.
61 hr
A sample of cigarette smoke contains 2.33% carbon monoxide. The U.S. national ambient air quality standard for CO in a 1−hr period is 35 ppm. How many times greater than this standard is the CO concentration in cigarette smoke?
666
if 500 mL of air contains 2x10^22 particles (atoms and molecules), how many particles do you inhale in one day if you breathe 15000 L of air?
6x10^26
calculate the percentage, by mass, of fluorine in sulfur hexafluoride (SF6), a potent greenhouse gas.
78.0 percent
how many carbon atoms does the molecule octane have?
8
although coal is a complex mixture of substances, its elemental composition can be approximated by the formula C135H96O9NS. Using this chemical formula, calculate the percentage, by mass, of carbon(c) in coal.
85 percent
consider the following equation that describes the complete combustion of propane, C3H8.
8554 kJ/mol
the quantity 8.7 x 10^5 g expressed in standard decimal notation
870,000 g
A certain combustion reaction generates 2.0 moles of carbon dioxide. How many grams does this represent? Report your number to one decimal place.
88.0 g
Express this concentration in terms of ppm: 0.0009%
9 ppm
how much energy is equivalent to 1.0x10^-4 kg of matter? (speed of light= 3.0x 10^8 m/s)
9.0x10^12J
in this photovoltaic (solar) cell, the n-type semiconductor is in the region labeled
B- electron
which reaction represents an acid-base neutralization reaction?
Be(OH)2+ H2SO4> BeSO4+ 2H2O
Using a table of alkanes as your guide, give the chemical formula for the straight-chain (normal) alkane with 12 carbon atoms.
C12H26
Give the chemical formula for the carbonate ion. Remember to include the charge.
CO(top)2- (bottom)3
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
fill in the table with the correct name for each polyatomic ion
CO3(2-); carbonate ClO-; hypochlorite NO3-; nitrate OH-; hydroxide NO2-; nitrite C2H3O2-; acetate
what is the chemical formula for carbon disulfide
CS2
give the chemical formula for calcium carbonate
CaCO3
in the famous equation E=mc2, the symbols represent
E=energy, m=mass, c=speed of light
which covalent bond is the most polar?
H-O
the - concentration in the air over the desert differs dramatically from that in the air in the tropical rainforest
H2O
categorize each compound as an HFC, CFC, HCFC or Halon (view answer in half screen)
HFC F H | | F- C - C - F | | F F H | F- C - H | F __________________ Halon F | Br- C- F | F _______________ CFC Cl | Cl-C-Cl | F Cl | F - C- Cl | F _______________ HCFC H | F - C - Cl | F Cl H | | F - C - C- H | | Cl H
categorize each compound as an HFC, CFC, HCFC or Halon
HFC- F F | | H-C - C -F | | F F H | F - C- H | F Halon- F | Br - C - F | F CFC- Cl | Cl - C - F | Cl Cl | Cl - C - F | F HCFC Cl | H- C - F | F H Cl | | H - C - C- F | | H Cl
which of the following compounds is useful for putting out fires and does not deplete stratospheric ozone concentrations
Halon-1211
which diagram(s) represent(s) only molecules?
I and II only (I -the one with 4 molecules joined) (II- the one where 2 exact molecules are joined)
consider these three compounds which are isomers?
I and III only
which argument(s) for the increasing use of solar energy is/are valid I. solar cells are becoming cheaper and increasingly more efficient II. the cost of generating electricity from fossil fuels is increasing III. limited and uncertain supply and the increasing requirements for pollution control are raising the cost of using fossil fuels
I, II, and III
lakes surrounded by - have very little acid-neutralizing capacity. I. marble II. granite III. limestone
II only
which diagram(s) best represent(s) only individual atoms
III only (single identical dots)
what international agreement attempted to reduce greenhouse gas emissions?
Kyoto protocol
which of the following compounds is considered to be an ionic compound
LiF
which one of the following compounds is considered to be an ionic compound
LiF
which concentration is consistent with a basic solution
MOH-=3.4x 10^-3M
what is the primary component of exhaled breath?
N2
which substance is not considered to be an air pollutant
N2
which is the balanced chemical equation for the reaction of nitrogen (N2) with oxygen (O2) to form NO?
N2+O2-->2NO
which of the following is a weak base
NH3
a proton released by an acid in aqueous solution quickly reacts with water to form a hydronium ion. what product is formed when a proton reacts with ammonia (NH3)?
NH4+
the chemical formula for nitrogen monoxide is
NO
which correctly pairs an indoor pollutant with its source
O3 and electrical arcing
bases produce which ions in aqueous solution
OH-
which shows the balanced equation for the reaction of nitrogen (dark O), as it is normally found in our atmosphere , with oxygen (white O), as it is normally found in our atmosphere, to form nitrogen dioxide?
OO(dark, nitrogen)+OO(white, oxygen+OO(white oxygen)--> O(white, oxygen)O(dark, nitrogen)O(white, oxygen) + O(white, oxygen)O(dark, nitrogen)O(white, Oxygen
which one of the following compounds is considered to be a molecular compound
PCl3
molecules and electromagnetic radiation interact. Atoms may dissociate, a molecule may rotate, or bonds may stretch and bend. Carbon dioxide has four possible vibrations. Select the true statements about the vibrations below.
Red molecule--><--Black molecule%% Red molecule--> -this vibration will change the charge distribution around the molecule. -this motion is called a stretching vibration -this vibration requires more energy -this vibration directly absorbs infrared radiation. Red molecule ^ Black molecule v Red molecule ^ -this vibration will change the charge distribution around the molecule -this motion is called a bending vibration - this vibration requires less energy -this vibration directly absorbs infrared radiation
which shows the lewis structure of water with the correct partial charges and nonbinding electrons?
S- : : O | | H H s+ s+
which of the following fission products released from the chernobyl reactor is dangerous because it concentrates in bones
Sr-90
how do mineral nanoparticles in sunscreens protect from UV radiation?
The particles absorb incoming UV light
which compounds are used in mineral-based sunscreens
ZnO and TiO2
when dissolved in water, hydrogen bromide (HBr) forms hydrobromic acid. Determine the hydroxide ion concentration in a 4,500 mL solution containing 3.78 g hydrogen bromide; Kw=1.00x10^-14
[OH-]=9.63x10 ^-13M
what is biological oxygen demand (BOD)?
a measure of the amount of dissolved oxygen microorganisms use up as they decompose organic wastes found in water
which of these is not a realistic risk associated with nuclear power plants
a nuclear explosion
in which example is the entropy of the initial state lower than the entropy of the final state
a pot of water boils to produce water vapor at 100C
in general, hydrogen bonds are
about 1/10 as strong as typical covalent bonds
when it reaches its largest size, the ozone hole over the antarctic is
about as large as north america
the energy needed to initiate a chemical reaction is called the
activation energy
the "doping" of a semiconductor to improve its performance means
adding small amounts of other elements to the pure semiconductor to change the freedom of electron motion throughout the crystal
decreased stratospheric ozone concentrations may lead to -harm to young marine life -increased incidences of melanomas -all of these choices are correct -an increased occurrence of cataracts
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? -human activities (primarily the combustion of fossil fuels and deforestation) are responsible for much of the recent warming -the earth is getting warmer -all of these choices were mentioned as key points -if the rate of greenhouse gas emissions is not curtailed, our water resources, food supply, and even our health will suffer
all of these choices were mentioned as key points
free radicals are - all of these correctly describe free radicals -species such as H. and .OH -highly reactive chemical species -species with unpaired electrons
all of these correctly describe free radicals
what type of radiation is given off in this nuclear reaction? 210Po84-->206Pb82 +
alpha
bases are substances that increase the hydroxide ion concentration in aqueous solution. Why does ammonia (NH3), which does not contain a hydroxide group, act as a base?
ammonia molecules remove protons from water molecules, forming hydroxide ions
what metal is used to dope an n-type semiconductor
arsenic
what is the relationship between stratospheric levels of atomic chlorine and ozone
as chlorine increases, ozone decreases
Is a solution with [OH−] = 1 ×10−6M acidic, basic or neutral?
basic
what type of radiation is given off in this nuclear reaction? 14C6-->14N7 + -
beta
which naturally occurring radioactive particles are negatively charged?
beta particles
which of these statements about biodiesel is not true -biodiesel can be used in diesel engines without major modifications -biodiesel has been withdrawn from several states due to health concerns -biodiesel is nontoxic and biodegradable -biodiesel is made from renewable resources such as vegetable oils and animal fats
biodiesel can be used in diesel engines without major modifications
which color in the rainbow has the shortest wavelength
blue
Which element is oxidized in this chemical reaction? 2Ca(s) + O2(g) →2CaO(s)
calcium
which compound is insoluble in water?
calcium carbonate
Give the number of carbon atoms, hydrogen atoms, and fluorine atoms in a molecule of HFC−32.
carbon atoms: 1 Hydrogen atoms: 2 fluorine atoms:2
what atmospheric component is responsible for the natural acidity of rain?
carbon dioxide
in general, which airborne material is not likely affected by the filters or indoor handling equipment?
carbon monoxide
given this diagram, this semiconductor is arsenic (pointing to a green molecule) silicon atom (pointing to a grey molecule) electron (pointing to a red dot)
carrying an extra electron
what is the role of polar stratospheric clouds (PSCs) on the destruction of ozone
chemical reactions occur on the clouds that convert molecules that do no damage to those that deplete ozone
which country is the world's leading producer of rare earth elements?
china
which product of the ultraviolet decomposition of CFCs acts as the catalyst for ozone decomposition?
chlorine atoms
which contributes to the ozone hole
chlorofluorocarbons (CFCs)
which is not a form of chlorine used to disinfect water
chloroform
currently, the primary source of sulfur dioxide emissions into the atmosphere is
coal burning power plants
which feature or process is unique to nuclear power plants when compared to conventional coal-burning power plants?
control rods
during petroleum refining, catalysts play an extremely important role during the
cracking and reforming processes
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
silicon has four electrons in its outer energy level, gallium has three. adding small amounts of gallium to pure silicon
creates a p-type semiconductor
what type of material is defined as having a well- ordered atomic structure?
crystalline
what type of material is defined as having a well-ordered atomic structure
crystalline
which of the following is not a drawback of using coal for energy production
difficult transportation due to instability
wavelength is the
distance between successive peaks in a wave
the process by which a solution is heated to its boiling point and the vapors are condensed and collected is known as
distillation
which type of water may be considered pure
distilled water
the first law of thermodynamics states that
energy is neither created nor destroyed
the measure of how much energy is dispersed in a given process is called the
entrophy
which is a correct statement of the second law of thermodynamics
entropy of the universe is constantly increasing
all zero greenhouse gas emission fuel sources are also renewable
false
the more toxic the pollutant, the higher the concentration is set when concerning air quality standards
false
which example is both a type of nuclear radiation and electromagnetic radiation
gamma radiation
which is produced in the greatest amount from a barrel of petroleum
gasoline
a gasoline's octane rating is a measure of the
gasoline's resistance to causing knocking in a vehicle's engine
HCFCs have been developed to replace CFCs as refrigerants. Which property of these new compounds makes them environmentally superior to CFCs?
greater reactivity leads to decomposition at elevations below the stratospheric ozone concentration maximum
single bonds, double bonds, and triple bonds
have 2, 4, and 6 shared electrons, respectively
which of these locations would be best suited to geothermal energy as a source to operate homes?
hawaii
the energy that flows from a warmer body to a colder body is called
heat
how is heat energy used to generate electricity in a modern power plant
heat boils water to make steam, which drives a turbine
in an exothermic chemical reaction
heat is released as the reaction proceeds
which conclusion was considered "very likely" in the 2014 report of the intergovernmental panel on climate change
human-caused emissions are the main factor causing warming since 1951
which conclusion was considered "very likely" in the 2014 report of the intergovernmental panel on climate change?
human-caused emissions are the main factor causing warming since 1951
petroleum (crude oil) is a complex mixture of thousands of substances, the majority of which are
hydrocarbons
which occurrences or processes are expected to reduce the level of atmospheric carbon? i. decaying plant and animal remains ii.the growth of trees iii. formation of carbonate rock in the ocean iv. animal respiration
ii and iii only
which substances are regulated by the kyoto protocol i. argon ii. carbon dioxide iii. nitrogen iv. nitrous oxide v. sulfur hexafluoride
ii, iv, and v only
the world map shows the availability of safe drinking water around the world. which statement is true?
in the United States and Canada, more than 90 percent of the population has access to clean water
where is most of the carbon on earth stored
in the form of fossil fuels and carbonate minerals and rocks
which is not true of radioactive half-life? radioactive half-life is
increased by heating the isotope
which is not a benefit associated with nuclear power plants
inexpensive to operate
the attractions between anions and cations throughout a crystal are known collectively as
ionic bonds
electronegativity
is a measure of an atom's attraction for an electron in a chemical bond
any chemical of physical change that absorbs energy
is an endothermic process
the C-H bond - the O-H bond
is less polar than
land use changes have a big impact on global warming because of their effects on albedo. albedo
is the ratio of electromagnetic radiation reflected by a surface to the amount of radiation hitting that surface
land use changes have a big impact on global warming because of their effects on albedo. Albedo
is the ratio of electromagnetic radiation reflected by a surface to the amount of radiation hitting that surface.
compounds with the same chemical formulas but different molecular structures are called
isomers
which is not a known advantage of natural gas over other fossil fuels
it is far more abundant than any other fossil fuel
in the petroleum industry, what does a refinery do
it separates crude oil into fractions consisting of compounds with similar boiling points
which unit is commonly used by utilities to measure the amount of electrical energy consumed?
kWh
the energy of motion is called - energy
kinetic
what sort of energy is associated with energy from wind
kinetic energy
which of the following is not an advantage of locating wind turbines off-shore instead of on land
maintenance costs are lower off-shore
use the chart below to relate the terms on the right.
matter | | pure substances mixtures | | elements compounds
the most numerous of the elements of the elements are the
metals
based on its name which carbon compound contains the fewest carbon atoms
methane
Classify the following compound as either molecular or ionic: XeF4
molecular
A(n) - is a fixed number of atoms held together by chemical bonds in a certain spatial arrangement
molecule
Give the name and chemical symbol for the element with 33 protons.
name: arsenic symbol: As
ozone is a secondary pollutant. a secondary pollutant is
not produced directly but as the product of the interaction of two or more pollutants
waste created at these power plants must be stored indefinitely
nuclear plants
which of the following has the lowest albedo
ocean
which of the following has the lowest albedo?
ocean
which of the following has the highest boiling point
octane
the burning of coal produces sulfur dioxide, SO2, a pollutant that slowly reacts in air to form SO3. sulfur trioxide dissolves into airborne water droplets to form a very corrosive solution of sulfuric acid. which is a product of burning coal that hastens the transformation of sulfur dioxide into sulfur tiroxide.
particles of ash
the burning of coal produces sulfur dioxide, SO2, a pollutant that slowly reacts in air to form SO3. sulfur trioxide dissolves into airborne water droplets to form a very corrosive solution of sulfuric acid. which is a product of burning coal that hastens the transformation of sulfur dioxide into sulfur trioxide
particles of ash
fill in the table with the correct formula for each polyatomic ion
phosphate- PO4(3-) sulfite- SO3(2-) Bicarbonate- HCO3- nitrate- NO3- hypochlorite- ClO- ammonium- NH4+
which type of renewable energy has most commonly been adapted for use on an individual home basis
photovoltaic
what is special about the south pole versus the north pole that leads to ozone depletion only at the south pole
polar stratospheric clouds form almost exclusively at the south pole
the energy stored in the chemical bonds of fossil fuels is a form of - energy
potential
which of the following is not seen as an advantage of increasing our use of solar energy
production and storage of solar energy is cost-efficient compared to fossil fuels
this illustration of an simplified atom highlights the three key subatomic particles. label each of them. assume the red particles are positively charged while the blue particles are neutrally charged
proton (on the left, inside cluster, red) electron-(top right, outside the cluster) neutron-(bottom right, inside cluster,blue)
which of the following is a subatomic particle located in the center of the atom and has a positive charge?
protons
the nucleus of an atom contains
protons and neutrons only
Using the periodic table as a guide, specify the number of protons and electrons in a neutral atom of krypton(Kr).
protons-36 electrons-36
Give the number of protons and neutrons in the nucleus of 12C.
protons-6 neutrons-6
Give the number of protons and neutrons in the nucleus of radon−222.
protons-86 neutrons- 136
we cannot effectively clean nonpolar substances from our hands or clothing with water alone; we must add soap or detergent. the structure of a typical soap molecule is shown below. which region of this molecule would dissolve in a nonpolar substance such as grease?
region 1 (biggest section)
the intergovernmental panel on climate change (IPCC) issued a report in 2014 that attached probabilities to the predictions and statements made. Which prediction/statement was considered "very unlikely?"
relative to 1850- 1900, the global surface temperature for the end of the 21st century (2081-2100) will exceed 2 deg C
the fact that carbon (C) is less electronegative than nitrogen (N) means that in a C-N bond, the
shared electrons are closer to the N atom than to the C atom.
which pollutant is present in air as particulate matter
soot
fission is the process of creating energy by
splitting large nuclei to form smaller, more stable nuclei
which is a common characteristic of both nuclear and conventional electric power plants
steam turbines
the conclusion that it is impossible to completely convert heat into work without making other changes in the universe is
the concept that increasing entropy characterizes all changes in the universe and the second law of thermodynamics
green chemistry is
the design of products and processes that reduce hazardous substances
how is wind energy related to the Sun
the heat of the sun drives large-scale movements of air
what distinguishes the atoms of one element from another
the number of protons
which compound should be the most soluble in water
the one with 4 rows
which common process on earth is endothermic
the production of oxygen by photosynthesis
what is the term used to describe a material that allows light to mostly pass through it?
transparent
the montreal protocol is a
treaty to reduce the amount of CFCs produced in the world
if we assume that the top of Mt. Everest is the highest land mass on earth, hikers who scale its summit are standing in the
troposphere
even thought the concentration of air pollution has gone down over time, people in some metropolitan areas still breathe air that contains unhealthy levels of pollutants
true
DNA, the genetic material of living organisms, is damaged by the light in the
ultraviolet region, especially below a wavelength of 320 nm.
which country has the highest per capita emission of carbon dioxide
united states
the internationally accepted atomic mass standard is carbon-12 because this isotope
was arbitrarily selected as a convenient standard
which source of renewable energy has seen the greatest growth in the last decade
wind
soft lignite (brown coal) is the lowest grade of coal. since it has undergone the least change since burial, its chemical composition- and hence its heat of combustion- is most similar to that of
wood
