Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
23.1 Multiple-Choice and Bimodal Questions
1) The oxidation state of copper in Cu 2CO3 (OH) 2 is __________.
A) 0
B) +1
C) +2
D) +4
E) -2
Answer: C
Diff: 2
Page Ref: Sec. 23.1
2) The oxidation state of copper in Cu 2S is __________.
A) +6
B) +2
C) +4
D) 0
E) +1
Answer: E
Diff: 2
Page Ref: Sec. 23.1
3) Melting an ore and causing the melt to separate into two or more layers is called
__________.
A) calcining
B) roasting
C) smelting
D) slag
E) alloying
Answer: C
Diff: 1
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
4) A thermal process that causes reactions between an ore and the atmosphere of the
furnace is called __________.
A) calcining
B) roasting
C) smelting
D) slag
E) refining
Answer: B
Diff: 1
Page Ref: Sec. 23.2
5) A slag is formed when a basic metal oxide reacts with molten __________ at high
temperatures.
A) Fe 2 O3
B) CaO
C) CaSiO3
D) SiO2
E) CO
Answer: D
Diff: 2
Page Ref: Sec. 23.2
6) Roasting HgS in the presence of oxygen produces the free metal and SO 2 . What is the
coefficient of HgS when the equation for this reaction is completed and balanced?
A) 1
B) 2
C) 3
D) 5
E) 4
Answer: A
Diff: 3
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
7) Carbon monoxide is commonly used to produce free metals from their oxides. What is
the coefficient of carbon monoxide in the balanced equation for the production of cobalt
from Co 2 O3 ?
A) 1
B) 2
C) 3
D) 5
E) 4
Answer: C
Diff: 3
Page Ref: Sec. 23.2
8) Roasting ZnS in the presence of oxygen produces the metal oxide and SO 2 . What is
the coefficient of ZnS when the equation for this reaction is completed and balanced?
A) 1
B) 2
C) 3
D) 5
E) 4
Answer: B
Diff: 3
Page Ref: Sec. 23.2
9) At high temperatures, carbon can be used as a reducing agent for metal oxides. What is
the coefficient of carbon in the balanced equation for the production of manganese and
CO 2 from manganese(II) oxide?
A) 1
B) 2
C) 3
D) 5
E) 4
Answer: A
Diff: 3
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
10) When carbon monoxide is used to reduce an ore as in a blast furnace, it is converted
to __________.
A) graphite
B) carbon dioxide
C) methane
D) carbonate
E) methanol
Answer: B
Diff: 4
Page Ref: Sec. 23.2
11) When hydrogen gas is used to reduce an ore (as in a blast furnace), it is converted to
__________.
A) ammonia
B) helium
C) hydrogen peroxide
D) water
E) hydroxide
Answer: D
Diff: 4
Page Ref: Sec. 23.2
12) The hydrometallurgical process used in refining gold ore entails converting metallic
gold to a water-soluble complex. The formula of the complex is __________.
A) Au(NH 3 ) 2
B) Au(CN) 43
C) Au(CN) 2
D) Au(CO) 4 2
E) Au(CO) 4
Answer: C
Diff: 4
Page Ref: Sec. 23.3
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
13) What is the product of the following (unbalanced) equation?
Al2 O3 H 2 O(s) H 2 O(l) OH (aq)
A) Al2 2H 2 O (s)
B) Al(OH)3 (s)
C) Al2 (OH)6 (s)
D) Al3 (aq)
E) Al(OH) 4 (aq)
Answer: E
Diff: 4
Page Ref: Sec. 23.3
14) Selectively dissolving a metal-containing compound from an ore is called
__________.
A) converting
B) sol formation
C) refining
D) oxidation
E) leaching
Answer: E
Diff: 2
Page Ref: Sec. 23.3
15) Processes used to reduce metal ores or to refine metals that are based on the process
of electrolysis are collectively referred to as __________.
A) pyrometallurgy
B) hydrometallurgy
C) electrometallurgy
D) calcination
E) roasting
Answer: C
Diff: 2
Page Ref: Sec. 23.4
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
16) The transition metals in group __________ have the highest melting points.
A) 4B
B) 3B
C) 6B
D) 8B
E) 2B
Answer: C
Diff: 3
Page Ref: Sec. 23.5
17) 18 karat gold contains __________% gold.
A) 18
B) 25
C) 89
D) 75
E) 1.0 x 102
Answer: D
Diff: 2
Page Ref: Sec. 23.6
18) 12 karat gold contains __________% gold.
A) 12
B) 25
C) 5.0 101
D) 75
E) 1.0 x 102
Answer: C
Diff: 2
Page Ref: Sec. 23.6
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
19) 24 karat gold contains __________% gold.
A) 24
B) 25
C) 5.0 101
D) 75
E) 1.00 102
Answer: E
Diff: 2
Page Ref: Sec. 23.6
20) 6.0 karat gold contains __________% gold.
A) 6.0
B) 25
C) 5.0 101
D) 75
E) 1.0 102
Answer: B
Diff: 2
Page Ref: Sec. 23.6
21) The maximum oxidation state in the first transition series is __________.
A) +2
B) +4
C) +5
D) +7
E) +8
Answer: D
Diff: 4
Page Ref: Sec. 23.7
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
22) In the second and third transition series, the maximum oxidation state is __________.
A) +2
B) +4
C) +5
D) +7
E) +8
Answer: E
Diff: 4
Page Ref: Sec. 23.7
23) Most of the compounds of copper in the __________ oxidation state are insoluble in
water.
A) +1
B) +2
C) +3
D) +7
E) +6
Answer: A
Diff: 3
Page Ref: Sec. 23.8
24) What is the coefficient of Cl2 when the following equation is completed and
balanced?
Cr2 O 7 2 (aq) Cl (aq) Cr 3 (aq) Cl 2 (g)
(acidic solution)
A) 1
B) 3
C) 5
D) 6
E) 4
Answer: B
Diff: 3
Page Ref: Sec. 23.8
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
25) What is the coefficient of Fe2 when the following equation is completed and
balanced?
Fe 2 H 2 O 2 Fe3 H 2 O
(acidic solution)
A) 1
B) 2
C) 3
D) 5
E) 4
Answer: B
Diff: 3
Page Ref: Sec. 23.8
26) The first step in the production of nickel from its ore, NiS, is to roast it in the
presence of oxygen to form the metal oxide and SO 2 . What is the coefficient of oxygen
when the equation for this reaction is completed and balanced?
A) 1
B) 2
C) 3
D) 5
E) 4
Answer: C
Diff: 5
Page Ref: Sec. 23.8
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
27) CuS has a very low solubility in water. However, it will dissolve in nitric acid due to
the following reaction.
CuS(s) NO3 (aq) Cu 2 (aq) S(s) NO(g)
(acidic solution)
What is the coefficient of CuS when this equation is balanced?
A) 1
B) 2
C) 3
D) 5
E) 4
Answer: C
Diff: 3
Page Ref: Sec. 23.8
23.2 Multiple-Choice Questions
1) A deposit that contains a metal in economically exploitable quantities is called a(n)
__________.
A) mineral
B) ore
C) vein
D) comstock
E) metal
Answer: B
Diff: 1
Page Ref: Sec. 23.1
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
2) Which of the following are not commonly used as sources of metals?
A) oxides
B) silicates
C) sulfides
D) carbonates
E) All of the above are commonly used sources of metals.
Answer: B
Diff: 1
Page Ref: Sec. 23.1
3) Chalcocite, chalcopyrite, and malachite are sources of which metal?
A) manganese
B) copper
C) titanium
D) iron
E) zinc
Answer: B
Diff: 2
Page Ref: Sec. 23.1
4) Which mineral contains titanium?
A) pyrolusite
B) chalcopyrite
C) galena
D) rutile
E) sphalerite
Answer: D
Diff: 2
Page Ref: Sec. 23.1
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
5) Which statement below is true?
A) New mining techniques and relatively untapped ore fields mean that the
environmental impacts of mineral extraction will decrease significantly in the future.
B) There exists little correlation between the abundance of an element in the lithosphere
and its commercial extraction and use.
C) Most metallic elements are found in the lithosphere in oxidation state zero.
D) The most important commercial class of minerals is the silicates.
E) The United States has plentiful ore fields of all strategic metals.
Answer: B
Diff: 2
Page Ref: Sec. 23.1
6) Which one of the following metallic elements is most likely to be found as the free
metal in nature?
A) Ca
B) Au
C) Al
D) Fe
E) Li
Answer: B
Diff: 2
Page Ref: Sec. 23.1
7) The undesirable material that is separated from an ore during the concentration process
is called __________.
A) gangue
B) leachate
C) slag
D) flocculent
E) silicate
Answer: A
Diff: 1
Page Ref: Sec. 23.1
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
8) The lithosphere is the
A) deepest part of the ocean.
B) portion of the atmosphere closest to the Earth.
C) molten core of the Earth.
D) portion of the atmosphere furthest from the Earth.
E) solid surface of the Earth.
Answer: E
Diff: 1
Page Ref: Sec. 23.1
9) Which mineral contains aluminum?
A) bauxite
B) malachite
C) cinnabar
D) galena
E) magnetite
Answer: A
Diff: 2
Page Ref: Sec. 23.1
10) Gold and the platinum group metals are found in nature in metallic form because
A) they are solids at room temperature.
B) they are highly reactive.
C) they are soluble in water.
D) they are relatively inert.
E) they are relatively abundant.
Answer: D
Diff: 1
Page Ref: Sec. 23.1
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
11) A mineral is
A) a solid inorganic compound that contains one or more metals.
B) a vitamin.
C) metal in its elemental form.
D) a transition metal ion.
E) source of carbon.
Answer: A
Diff: 1
Page Ref: Sec. 23.1
12) An alloy is a
A) heterogeneous mixture of two metals.
B) pure metal.
C) metallic material that is composed of two or more elements.
D) nonmetal with some properties of a metal.
E) a mineral containing two or more metals.
Answer: C
Diff: 1
Page Ref: Sec. 23.1
13) Metallurgical processes that utilize high temperatures are collectively called
__________.
A) hydrometallurgy
B) pyrometallurgy
C) electrometallurgy
D) alloying
E) roasting
Answer: B
Diff: 1
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
14) The process of heating an ore to decompose it and release any volatile products is
referred to as __________.
A) roasting
B) smelting
C) refining
D) calcination
E) alloying
Answer: D
Diff: 1
Page Ref: Sec. 23.2
15) The purpose of a converter in steel production is __________.
A) to reduce the iron in the ore to elemental
B) to remove impurity elements by oxidation
C) to allow the formation of phosphides within the metal for added corrosion resistance
D) to allow the addition of nitrogen for increased strength
E) to allow slow solidification of the molten metal so it will purify as it crystallizes
Answer: B
Diff: 2
Page Ref: Sec. 23.2
16) What is produced when a carbonate is calcined?
A) the free metal and sodium carbonate
B) the free metal and sulfur dioxide
C) the metal oxide and carbon dioxide
D) water and the metal hydride
E) the free metal and carbon dioxide
Answer: C
Diff: 3
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
17) During roasting, the metal reacts with __________.
A) oxygen
B) carbon monoxide
C) sulfur
D) the furnace atmosphere
E) iron
Answer: D
Diff: 3
Page Ref: Sec. 23.2
18) Why is either pure oxygen or oxygen diluted with argon used in a converter instead
of air?
A) The carbon dioxide in air will cause the iron to oxidize and form rust.
B) The oxygen concentration is too low to function efficiently at removing impurities.
C) The carbon monoxide in air reacts with the iron to form a volatile, and toxic, iron
carbonyl.
D) The nitrogen in air will react with iron to form iron nitride that will make the iron
brittle.
E) Because it's cheaper.
Answer: D
Diff: 3
Page Ref: Sec. 23.2
19) What happens to the silicon that is a contaminant in crude iron in a converter?
A) it is converted to the tetrafluoride that bubbles out as a gas.
B) It is precipitated as sodium silicate.
C) It is converted to silicon dioxide and becomes part of the slag.
D) It is precipitated as the carbide.
E) It is precipitated as iron silicate.
Answer: C
Diff: 3
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
20) In the reduction of iron in a blast furnace, limestone is a source of __________ which
reacts with silicates and other components of the ore to form __________.
A) coke; carbon monoxide
B) hematite; pig iron
C) calcium oxide; slag
D) magnetite; steel
E) calcium; molten iron
Answer: C
Diff: 2
Page Ref: Sec. 23.2
21) Which reaction controls the temperature of a blast furnace?
A) 2C O 2 2CO 2
B) C H 2O CO H 2
C) CaO SiO2 CaSiO3
D) Fe3O4 4CO 3Fe 4CO 2
E) CaCO3 CaO CO2
Answer: B
Diff: 3
Page Ref: Sec. 23.2
22) Roasting of the disulfide of molybdenum in O 2 produces which products
A) MoO3 (s) SO 2 (g)
B) Mo(s) SO2 ( g)
C) MoO3 (s) SO 2 (g)
D) MoO3 (s) SO3 (g)
E) Mo(s) MoS(s) SO2 (g)
Answer: C
Diff: 3
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
23) A basic slag is needed in steelmaking to
A) remove SiO2 as silicates.
B) reduce any nitrogen-containing compounds to N 2 .
C) react with any BrØnsted Lowry acids present.
D) provide CaO to remove phosphorus oxides as Ca 3 (PO 4 ) 2 .
E) oxidize any carbon-containing compounds to CO 2 .
Answer: D
Diff: 3
Page Ref: Sec. 23.2
24) Smelting is
A) melting and subsequent reaction of molten ores resulting in the formation of layers.
B) heating an ore to make it react with a gas in a furnace.
C) thermal decomposition of an ore with elimination of a gaseous product.
D) addition of calcium to a molten ore.
E) cooling a molten metal to make it solidify.
Answer: A
Diff: 2
Page Ref: Sec. 23.2
25) Which of the following equations represents a calcination?
A) HgS(s) O2 (g) Hg(g) SO2 (g)
B) PbCO3 (s) PbO(s) CO2 (g)
C) PbO(s) CO(g) Pb(l) CO2 (g)
D) CaO(l) SiO2 (l) CaSiO3 (l)
E) All of the above are calcination processes.
Answer: B
Diff: 3
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
26) Which of the following equations represents the roasting of an ore?
A) All of these represent roasting processes.
B) HgS(s) O2 (g) Hg(g) SO2 (g)
C) PbO(s) CO(g) Pb(l) CO2 (g)
D) 2ZnS(s) 3O2 (g) 2ZnO(s) 2SO2 (g)
E) 2MoS2 (s) 7O2 (g) 2MoO3 (s) 4SO 2 (g)
Answer: A
Diff: 3
Page Ref: Sec. 23.2
27) The purpose of burning coke in a blast furnace is
A) to produce reducing gases.
B) to produce heat.
C) to produce carbon monoxide gas.
D) to produce hydrogen gas.
E) all of the above
Answer: E
Diff: 3
Page Ref: Sec. 23.2
28) A mixture of oxygen and argon are blown through molten iron that is produced in a
blast furnace for the purpose of
A) completing the reduction of iron.
B) oxidizing the iron before it cools.
C) cooling the molten iron.
D) removing carbon, sulfur, and other impurities.
E) removing other metals.
Answer: D
Diff: 3
Page Ref: Sec. 23.2
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
29) Steel is
A) an alloy of iron.
B) pure iron.
C) oxidized iron.
D) a mixture of iron and silver.
E) a liquid at room temperature.
Answer: A
Diff: 2
Page Ref: Sec. 23.2
30) Hydrometallurgy is
A) the use of water to cool molten metals.
B) the use of high temperature processes to concentrate and refine metals.
C) the use of water to locate underground ore deposits.
D) the use of aqueous solutions to extract metals from their ores.
E) the use of high temperature processes to make alloys.
Answer: D
Diff: 2
Page Ref: Sec. 23.3
31) What are the products of the following (unbalanced) leaching process?
Au(s) CN (aq) O 2 (g) H 2O(l)
A) Au(CN)3 (s) and OH (aq)
B) AuCN(s) and OH (aq)
C) AuCN (s) and H 2O2 (aq)
D) Au(CN) 4 (aq) and OH (aq)
E) Au(CN) 2 (aq) and OH (aq)
Answer: E
Diff: 3
Page Ref: Sec. 23.3
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
32) An advantage to leaching gold with aqueous solutions of cyanide ion is that
A) the process requires only one step.
B) the gold recovered in this way has higher purity than gold recovered in other ways.
C) the method can be used to locate underground gold deposits.
D) gold can be recovered from very low-grade ores by this method.
E) the process is environmentally safe.
Answer: D
Diff: 3
Page Ref: Sec. 23.3
33) A disadvantage to leaching gold with aqueous solutions of cyanide ion is that
A) it requires the use of ores with a very high concentration of gold.
B) the method does not produce gold of high enough purity.
C) the method is a potential environmental hazard.
D) sodium cyanide is very expensive.
E) it is a complicated process requiring more than two dozen separate steps.
Answer: C
Diff: 3
Page Ref: Sec. 23.3
34) The major impurities found in bauxite are __________.
A) SiO2 and Fe 2 O3
B) Al2 O3 and H 2 O
C) Fe and H 2 O
D) Al2 O3 and OH
E) carbon and salicylic acid
Answer: A
Diff: 3
Page Ref: Sec. 23.3
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
35) Which one of the following is false concerning the Bayer Process?
A) It is a hydrometallurgical process.
B) It involves treatment of bauxite with cold, dilute sodium hydroxide solution.
C) In the process, aluminum is converted to a soluble aluminate ion.
D) It results in the separation of aluminum from iron and silicon.
E) It is used to purify bauxite.
Answer: B
Diff: 3
Page Ref: Sec. 23.3
36) Part of the Bayer process involves the digestion of crushed ore in concentrated
aqueous sodium hydroxide. This process carried out at high pressure __________.
A) to prevent boiling
B) to prevent formation of iron hydroxide
C) to prevent formation of aluminum hydroxide
D) to accelerate formation of iron hydroxide
E) to lower the boiling temperature of the mixture
Answer: A
Diff: 3
Page Ref: Sec. 23.3
37) The metal __________ is extracted from __________ ore by the Bayer process.
A) iron; magnetite
B) mercury; cinnabar
C) tin; casserite
D) aluminum; bauxite
E) zinc; sphalerite
Answer: D
Diff: 1
Page Ref: Sec. 23.3
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
38) What is the purpose of adding zinc powder to a solution of Au(CN) 2 ?
A) to precipitate the cyanide-gold complex
B) to reduce the gold in the cyanide complex to gold metal
C) to precipitate the cyanide ion
D) to oxidize the gold in the cyanide complex to gold metal
E) to form a gold-zinc alloy
Answer: B
Diff: 3
Page Ref: Sec. 23.3
39) In the Bayer process, the purpose of filtration after the ore has been digested in
concentrated sodium hydroxide is __________.
A) to separate the soluble aluminum complex from the insoluble iron impurities
B) to separate the insoluble aluminum oxide from the soluble iron impurity
C) to separate the aluminum metal from the hydroxide ions
D) to remove the sodium ions from the sodium hydroxide solution
E) to remove the anode sludge
Answer: A
Diff: 3
Page Ref: Sec. 23.3
40) In the Bayer process, the purpose of lowering the pH after the digested ore has been
filtered is __________.
A) to precipitate the iron hydroxide
B) to precipitate the iron oxide
C) to precipitate the aluminum hydroxide
D) the dissolve the remaining ore
E) to dissolve the remaining impurities
Answer: C
Diff: 3
Page Ref: Sec. 23.3
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
41) The anode sludges from copper refining are important sources of what metal(s)?
A) gold
B) silver
C) aluminum
D) both A and B
E) all of the above
Answer: D
Diff: 3
Page Ref: Sec. 23.4
42) The Hall process is
A) the pyrometallurgic process used to produce iron.
B) the pyrometallurgic process used to produce aluminum.
C) the electrolytic process used to produce aluminum.
D) the hydrometallurgic process to produce aluminum.
E) the electrolytic process used to produce iron.
Answer: C
Diff: 3
Page Ref: Sec. 23.4
43) The product in the Hall electrometallurgical process is
A) copper.
B) iron.
C) aluminum.
D) gold.
E) silver.
Answer: C
Diff: 3
Page Ref: Sec. 23.4
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
44) The respective standard oxidation potentials for Cu Cu 2 , Ni Ni 2 , and
Ag Ag are (in V) -0.34, +0.28and -0.80. Impure copper slabs at the anode are refined
electrochemically, affording much purer metallic copper at the cathode. Which statement
below is true?
A) Cu is oxidized preferentially over both Ni and Ag, so both Ni and Ag metals are
separated as sludges below the anode.
B) Ni is oxidized preferentially over Cu, and Ni 2 is reduced much less readily than
Cu 2 , so Ni is separated as Ni 2 in the electrolyte solution.
C) Ag is oxidized preferentially over Cu, and Ag is reduced much less readily than
Cu 2 , so Ag is separated as Ag in the electrolyte solution.
D) Ag is oxidized preferentially over Cu, and Ag is reduced much more readily than
Cu 2 , so Ag plates out with Cu at the cathode and cannot readily be removed from
impure copper.
E) Both Ni and Ag are oxidized preferentially over Cu and Ni 2 , and Ag is reduced
much less readily than Cu 2 , so Ni and Ag are separated as Ni 2 and Ag in the
electrolyte solution.
Answer: B
Diff: 5
Page Ref: Sec. 23.4
45) In the Bayer process, what is the product of calcination of the aluminum hydroxide
recovered from the digestion in base?
A) Al ∙ xH2O(s)
B) Al (s)
C) Al(OH)3 (s)
D) Al2 O3 (s)
E) Al(OH) 4 (aq)
Answer: D
Diff: 4
Page Ref: Sec. 23.4
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
46) Anhydrous aluminum oxide is dissolved in molten cryolite rather than simply melted
because __________
A) the cryolite actually provides the aluminum that is to be reduced.
B) the cryolite provides a source of sodium ions.
C) the melting point of pure, anhydrous aluminum oxide is too high.
D) in pure, molten Al2 O3 , the aluminum would be oxidized rather than reduced.
E) the cryolite provides the necessary fluoride ions.
Answer: C
Diff: 4
Page Ref: Sec. 23.4
47) Calcium chloride is added to sodium chloride prior to melting it for electrolysis in a
Downs cell __________.
A) to lower the melting point
B) to increase the concentration of chloride ions
C) to make the sodium ions easier to reduce
D) to make the chloride ions easier to oxidize
E) to provide calcium ions which serve as the cathode
Answer: A
Diff: 4
Page Ref: Sec. 23.4
48) Sodium metal cannot be produced by electrolysis of an aqueous solution of sodium
chloride because __________
A) the carbon anode is more easily reduced than sodium ions.
B) water is more easily oxidized than sodium metal.
C) the production of chlorine gas interferes with the reduction of sodium ions.
D) the iron cathode would be corroded by the salt water.
E) water is more easily reduced than sodium ions.
Answer: E
Diff: 4
Page Ref: Sec. 23.4
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
49) Which property of metals cannot be explained with the electron-sea model?
A) shine
B) high thermal conductivity
C) high electric conductivity
D) malleability and ductility
E) trends in melting points
Answer: E
Diff: 3
Page Ref: Sec. 23.5
50) Transition metals have energy bands composed of two states, low energy and high
energy. What elements have filled low energy states and empty high energy states?
A) Ti, Zr, Hf
B) Cr, Mo, W
C) Co, Rh, Ir
D) Cu, Ag, Au
E) Zn, Cd, Hg
Answer: B
Diff: 3
Page Ref: Sec. 23.5
51) Which one of the following is a property of most metals?
A) low melting point
B) brittleness
C) high electronegativity
D) thermal conductivity
E) acidic oxides
Answer: D
Diff: 2
Page Ref: Sec. 23.5
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
52) The molecular-orbital model for Ge shows it to be
A) a conductor, because all the lower energy band orbitals are filled and the gap between
the lower and higher bands is large.
B) an insulator, because all the lower energy band orbitals are filled and the gap between
the lower and higher bands is large.
C) a semiconductor, because the gap between the filled lower and empty higher energy
bands is relatively small.
D) a semiconductor, because the gap between the filled lower and empty higher energy
bands is large.
E) a conductor, because its lower energy band orbitals are only partially filled.
Answer: C
Diff: 5
Page Ref: Sec. 23.5
53) If the electronic structure of a solid substance consists of a valence band that is
completely filled with electrons and there is a large energy gap to the next set of orbitals,
then this substance will be a(n) __________.
A) alloy
B) insulator
C) conductor
D) semiconductor
E) nonmetal
Answer: B
Diff: 4
Page Ref: Sec. 23.5
54) Which statement about steel is false?
A) It is a polymer.
B) It is an alloy of iron.
C) It can have different percentages of carbon.
D) It can be made so it resists rust.
E) none of the above
Answer: A
Diff: 2
Page Ref: Sec. 23.1, 23.6
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
55) For a substitutional alloy to form, the two metals combined must have similar
A) ionization potential and electron affinity.
B) number of valance electrons and electronegativity.
C) reduction potential and size.
D) atomic radii and chemical bonding properties.
E) band gap and reactivity.
Answer: D
Diff: 4
Page Ref: Sec. 23.6
56) What is the typical effect of the addition of an interstitial element on the properties of
a metal?
A) increase in malleability and corrosion resistance
B) increase in hardness and strength, decrease in ductility
C) decrease in melting point and increase in ductility
D) decrease in conductivity and increase in brittleness
E) increased surface luster
Answer: B
Diff: 3
Page Ref: Sec. 23.6
57) Heterogeneous alloys
A) do not have uniform composition throughout.
B) have properties that depend on composition.
C) have properties that depend on the manner in which the melt is solidified.
D) have properties that depend on the manner in which the solid is formed.
E) All of the above are true.
Answer: D
Diff: 3
Page Ref: Sec. 23.6
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
58) Intermetallic compounds are examples of
A) homogeneous alloys.
B) heterogeneous alloys.
C) interstitial alloys.
D) solution alloys.
E) ionic compounds.
Answer: A
Diff: 2
Page Ref: Sec. 23.6
59) Which of the following is not an alloy?
A) brass
B) steel
C) sterling silver
D) dental amalgam
E) ceramic
Answer: E
Diff: 3
Page Ref: Sec. 23.6
60) Alloys generally differ from compounds in that
A) the former always contain some carbon.
B) the former always contain some iron.
C) the former always have semiconductor properties.
D) the atomic ratios of the constituent elements in the former are not fixed and may vary
over a wide range.
E) the former never contain a transition element.
Answer: D
Diff: 3
Page Ref: Sec. 23.6
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
61) Which element is typically not added to steel to modify its properties?
A) carbon
B) vanadium
C) chromium
D) nitrogen
E) nickel
Answer: D
Diff: 3
Page Ref: Sec. 23.6
62) Shape memory alloys __________.
A) change their structure as the temperature changes
B) in their lower temperature phase have a flexible arrangement between atoms
C) in their higher temperature phase have strong and fixed bonds between atoms
D) are more pliable when cold than when warm
E) all of the above
Answer: E
Diff: 3
Page Ref: Sec. 23.6
63) Of the following, which is a bulk property?
A) electron configuration
B) ionization energy
C) melting point
D) atomic radius
E) atomic number
Answer: C
Diff: 3
Page Ref: Sec. 23.7
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
64) What two oxidation states are more frequently observed in the first transition series
than in the third?
A) +3 and +7
B) +2 and +3
C) +2 and +7
D) +5 and +6
E) +3 and +5
Answer: B
Diff: 4
Page Ref: Sec. 23.7
65) Salts of which of the following transition metals are orange?
A) Mn 2
B) Zn 2
C) Ni 2
D) Co2
E) Fe2
Answer: D
Diff: 3
Page Ref: Sec. 23.7
66) A substance with unpaired electrons will be
A) slightly attracted to a magnet.
B) slightly repelled by a magnet.
C) permanently magnetic.
D) brightly colored.
E) nonmetallic.
Answer: A
Diff: 3
Page Ref: Sec. 23.7
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
67) The lanthanide contraction is responsible for the fact that
A) Zr and Y have about the same radius.
B) Zr and Nb have similar oxidation states.
C) Zr and Hf have about the same radius.
D) Zr and Zn have similar oxidation states.
E) Zr and Hf have the same oxidation states.
Answer: C
Diff: 3
Page Ref: Sec. 23.7
68) Which one of the following is not true about transition metals?
A) They frequently have more than one common oxidation state.
B) Their compounds are frequently colored.
C) Their compounds frequently exhibit magnetic properties.
D) They are found in the d-block of the periodic table.
E) They typically have low melting points.
Answer: E
Diff: 3
Page Ref: Sec. 23.7
69) Reaction of iron with which one of the following acids will result in the direct
production of Fe3 ?
A) HNO3
B) HCl
C) HI
D) CH 3COOH
E) dilute H 2SO4
Answer: A
Diff: 3
Page Ref: Sec. 23.8
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
70) Which one of the following copper compounds is black in color?
A) CuI
B) CuSO 4
C) Cu(H 2 O) 4 2
D) CuCl2
E) CuO
Answer: E
Diff: 3
Page Ref: Sec. 23.8
71) Which of the following copper compounds prevents algae growth?
A) CuS
B) CuSO 4
C) Cu(OH) 2
D) Cu(NO3 ) 2
E) CuCl2
Answer: B
Diff: 2
Page Ref: Sec. 23.8
72) A small amount of barium chloride solution is added to a blue solution. A white
precipitate forms. The blue solution contains
A) NiSO 4
B) CuCl2
C) CuSO 4
D) Cu(NO 3 )3
E) CoCl2
Answer: C
Diff: 4
Page Ref: Sec. 23.8
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
73) When copper(II) hydroxide is heated, __________ and __________ are formed.
A) Cu(s), H 2 O(l)
B) CuO(s), H 2 O(l)
C) Cu(s), OH (g)
D) CuOH(s) H 2 O(g)
E) CuH 2 (s) O 2 (g)
Answer: B
Diff: 3
Page Ref: Sec. 23.8
74) Which one of the following compounds is yellow?
A) Cr(NO3 )3
B) CrCl3
C) K 2CrO4
D) (NH 4 ) 2 Cr2 O 7
E) CCl2
Answer: C
Diff: 3
Page Ref: Sec. 23.8
75) An aqueous solution of Fe(NO3 )3 will slowly form a red-brown precipitate due to the
formation of __________.
A) Fe(OH)3
B) Fe3O 4
C) FeO
D) Fe(OH) 2
E) FeO 2
Answer: A
Diff: 3
Page Ref: Sec. 23.8
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
76) The hydrated nickel(II) ion is
A) orange.
B) blue.
C) yellow.
D) green.
E) colorless.
Answer: D
Diff: 3
Page Ref: Sec. 23.8
77) The hydrated manganese(II) ion is
A) orange.
B) blue.
C) yellow.
D) violet.
E) colorless.
Answer: E
Diff: 3
Page Ref: Sec. 23.8
23.3 Short Answer Questions
1) Give the name and formula of the two important ores of iron.
Answer: hematite, Fe 2 O3 , and magnetite, Fe3O 4
Diff: 2
Page Ref: Sec. 23.1
2) What is the name and the formula of the most useful ore of aluminum?
Answer: bauxite, Al2 O3 xH 2 O
Diff: 2
Page Ref: Sec. 23.1
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
3) Write the two reactions that are used to control the temperature in a blast furnace and
indicate which provides heat and which cools.
Answer 2C(s) O 2 (g) 2CO(g) , provides heat
C(s) H 2O(g) CO(g) H 2 (g) , cools
Diff: 4
Page Ref: Sec. 23.2
4) A material that contains more than one element and has the characteristic properties of
metals is called a (an) __________.
Answer: alloy
Diff: 2
Page Ref: Sec. 23.6
5) What two metals are alloyed to produce sterling silver?
Answer: silver and copper
Diff: 4
Page Ref: Sec. 23.6
6) Most of the metals in the third transition series have about the same atomic radius as
the elements above them in second transition series. This is a result of __________.
Answer: the lanthanide contraction
Diff: 4
Page Ref: Sec. 23.7
7) Draw a diagram of the short-hand ground state electron configuration of zinc.
Answer:
[Ar]
Diff: 4
Page Ref: Sec. 23.7
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
8) Most transition metal ions contain partially occupied __________ subshells.
Answer: d
Diff: 3
Page Ref: Sec. 23.7
9) A substance is __________ if its ions or atoms have one or more unpaired electrons.
Answer: paramagnetic
Diff: 1
Page Ref: Sec. 23.7
10) The two more common oxidation states of chromium are __________ and
__________.
Answer: 3+; 6+
Diff: 3
Page Ref: Sec. 23.7
11) __________ arises when the unpaired electrons of the atoms or ions in a solid are
influenced by the orientations of the electrons of their neighbors.
Answer: Ferromagnetism
Diff: 3
Page Ref: Sec. 23.8
12) The condensation reaction of chromic acid produces __________ and __________.
Answer: dichromate ion; water
Diff: 3
Page Ref: Sec. 23.8
13) Iron often appears in natural waters because dissolved CO 2 and water come in contact
with deposits of __________.
Answer: FeCO 3
Diff: 2
Page Ref: Sec. 23.8
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
14) Fe(OH)3 precipitates from Fe(H 2 O)63 by making the solution more __________.
Answer: basic
Diff: 2
Page Ref: Sec. 23.8
23.4 True/False Questions
1) Gangue is the unwanted material that accompanies an ore when it is mined.
Answer: True
Diff: 1
Page Ref: Sec. 23.1
2) Calcining is the heating an ore to bring about the elimination of calcium salts.
Answer: False
Diff: 2
Page Ref: Sec. 23.2
3) The purpose of the limestone used in a blast furnace is to form slag.
Answer: True
Diff: 2
Page Ref: Sec. 23.2
4) In a blast furnace, coke is used to provide the needed heat and to provide carbon
monoxide to act as a reducing agent.
Answer: True
Diff: 2
Page Ref: Sec. 23.2
5) Many metals are ductile, which means that they can be hammered into thin sheets.
Answer: False
Diff: 2
Page Ref: Sec. 23.5
Chemistry, 11e (Brown/LeMay/Brusten/Murphy)
Chapter 23: Metals and Metallurgy
6) Chromium is in the +6 oxidation state in both chromate and dichromate anions.
Answer: True
Diff: 3
Page Ref: Sec. 23.8