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A) cost of mining and transporting the ore
B) cost of environmental maintenance
C) cost of extracting the metal
D) All of the above must be considered.
53) Steel, in all of its variations, is a(n)
A) alloy.
B) compound.
C) element.
D) pure substance.
54) Bronze is an alloy of
A) aluminum and tin.
B) copper and tin.
C) lead and copper.
D) platinum and palladium.
55) Iron is so abundant and useful that it accounts for roughly ________ of the world’s metal production.
A) 10 %
B) 35 %
C) 65%
D) 95 %
56) Which of the following statements about the corrosion of iron and aluminum is correct?
A) Aluminum reacts with oxygen to form an Al2O3 coating, which can flake off easily and allow more
aluminum to undergo corrosion.
B) Iron reacts with oxygen to form an Fe2O3 coating, which can flake off easily and allow more iron to
undergo corrosion.
C) Both aluminum and iron react with oxygen to form oxides which are hard and protect the metal from
corrosion.
D) Aluminum corrodes more rapidly than iron does because it is lighter.
57) Recycling aluminum cans requires ________ percent of the energy of making a new beverage can.
A) 10
B) 30
C) 50
D) 5
58) Steel is an alloy that always contains which metal?
A) aluminum
B) copper
C) iron
D) lead
59) Which of the following statements about technologically important elements is true?
A) China has a virtual monopoly on the rare earth metals.
B) The U.S. still has large deposits of high-grade ores.
C) It requires more energy to extract these metals from high-grade ores than from low-grade ores.
D) The U.S. and other industrial nations are nearly 100% self-sufficient for these metals.
60) If we should “run out” of aluminum someday, it would be because we had
A) converted too much aluminum to another metal.
B) destroyed too much aluminum.
C) used too much aluminum.
D) scattered aluminum too widely in the environment for efficient recovery.
61) Which of the following metals does the United States import from other countries?
A) indium
B) lithium
C) palladium
D) All of the above are imported from other countries.
62) The largest percentage of solid waste in municipal solid waste is
A) glass.
B) paper and cardboard.
C) metals.
D) plastics.
63) What is NOT true of plastic bags?
A) They are recyclable.
B) They take a while to break down.
C) They do not harm wildlife.
D) They are made from petroleum.
64) New processes in solid waste disposal include
A) using a mixture of ground up tires and powdered coal as fuel.
B) adding waste glass and rubber tires to road-paving mixtures for use in road construction.
C) converting garbage to oil.
D) All of the above are new processes for waste disposal.
65) The best way to handle solid waste is to
A) incinerate it.
B) dump it at sea.
C) bury it.
D) reduce it, reuse it and recycle it.
66) 1.00 kilogram of polyethylene produces about the same energy as ________ kg of no. 2 fuel oil.
A) 1.00
B) 0.50
C) 0.25
D) 1.25
67) Which of the following has the highest recycling rate?
A) plastic soft drink bottles
B) steel food cans
C) glass bottles
D) aluminum cans
68) When scrap metal is recycled to make new iron and steel products, there is also a reduction in
A) energy consumption.
B) water pollution.
C) air pollution.
D) All of the above are reduced.
69) The approximate human population of Earth is more than
A) 2 billion.
B) 12 billion.
C) 7 billion.
D) 10 billion.
70) At the present rate of growth, world population will be approximately ________ billion by 2045.
A) 13
B) 9
C) 16
D) 5
71) Which of the following has resulted from the increase in world population?
A) better recycling
B) an increase in waste generation
C) more plentiful water
D) more food
72) Which of the following has led to a rapid increase in the world’s population since 1900?
A) an increase in the birth rate
B) a decrease in the birth rate
C) an increase in the death rate
D) a decrease in the death rate
73) Which of the following is NOT a potential problem with a sanitary landfill?
A) A landfill may leak and contaminate groundwater.
B) Materials in a landfill decompose more slowly than materials that are exposed to environmental
conditions.
C) The landfill will eventually fill up.
D) All of the above are potential problems of landfills.
74) Using hydrogen (H2) to reduce magnetite (Fe3O4) to iron (Fe) is considered to be “greener” than using
carbon monoxide (CO) because
A) there are more molecules of the CO2 by-products produced than molecules of the water by-product.
B) water contributes less to climate change than carbon dioxide does.
C) using hydrogen uses much less energy than using carbon monoxide does.
D) the iron produced by using hydrogen can be replaced by aluminum more easily.
75) Every day, the world population goes up by
A) 300,000 people.
B) 200,000 people.
C) half a million people.
D) a million people.
12.2 True/False Questions
1) The earth’s mantle is primarily composed of carbonates.
2) The most abundant element in the earth’s surface is aluminum.
3) One of the more common rocks on earth is limestone.
4) The organic portion of the earth’s lithosphere is greater than the inorganic part.
5) Fire was one of the earliest agents that enabled chemical changes.
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6) Quartz is pure silicon dioxide.
7) The harmful effects of asbestos include mesothelioma.
8) Pure quartz is colorless.
9) Ceramics are formed by heating a mixture of sand, sodium carbonate and limestone.
10) Ceramics are made by heating inorganic materials to a high temperature so that the particles partially
melt and fuse together.
11) The raw materials for the production of cement are limestone and clay.
12) Adding chromium compounds will give glass a green color.
13) Glass does not degrade in the environment, but it is easy to recycle.
14) The ore from which aluminum metal is extracted is bauxite.
15) It takes less energy to produce a pound of aluminum than it does to produce a pound of steel.
16) Low-grade ores are undesirable because extracting the metals requires more energy per pound than
high-grade ores.
17) Aluminum is more reactive than iron, so an aluminum bar will corrode more quickly than an iron bar.
18) The properties of steel can be altered by the addition of metals, such as manganese or chromium, to
the alloy.
19) China produces most of the rare earth metals in the world.
20) In the United States, there are adequate reserves of high-grade ores of iron and copper.
21) The United States imports almost no metals from foreign countries.
22) Lithium is typically used for batteries for tools, laptop computers, and cell phones.
23) Plastics form the largest proportion of solid waste in the average sanitary landfill.
24) The best way to dispose of municipal solid waste is to incinerate it, because incinerators do not
produce air pollution.
25) Replacing steel with aluminum whenever possible will minimize harm to the environment.
26) Recycling steel cans is more economical than recycling aluminum cans.
12.3 Essay Questions
1) What is a synergistic effect? Use asbestos and cigarette smoking as an example.
2) Although cement and concrete themselves are relatively non-polluting, their production and use are a
source of several potential environmental problems. Describe two examples.
3) The “coking” process in steel making is a significant source of pollution. Why? What are some
alternatives to “coke?”
4) List two additional important metals, not including Fe, Cu and Al, and their uses.
5) Discuss energy advantages of using more aluminum and less steel in the construction of a car.