Deck 23: Metallurgy and the Chemistry of Metals

Question 1

What elements are alloyed to make stainless steel?

A)Fe and C
B)Fe and Mn
C)Fe and Ni
D)Fe and Cr
E)Fe,Cr,and Ni

Answer 1

Fe,Cr,and Ni

Question 2

Electrometallurgy uses _________________ to separate a metal from its ore.

A)solid phase chemical properties
B)electrical processes
C)thermal processes
D)aqueous chemical processes
E)molten salt processes

Answer 2

electrical processes

Question 3

Which of these reactions represents the removal of silica from iron ore in a blast furnace?

A)SiO₂(s)→ SiO₂(g)
B)SiO₂(s)+ CaO(s)→ CaSiO₃(l)
C)SiO₂(s)+ 4HF(g)→ SiF₄(g)+ 2H₂O(g)
D)SiO₂(s)+ C(s)→ Si(l)+ CO₂(g)
E)SiO₂(s)+ CO(g)→ SiCO₃(l)

Answer 3

SiO₂(s)+ CaO(s)→ CaSiO₃(l)

Question 4

The process that selectively extracts a metal from its ore,by dissolving it,is called

A)roasting.
B)leaching.
C)smelting.
D)flotation.
E)hydration.

Question 5

Alloying a metal is done to

A)make its extraction from its ore easier.
B)convert the metal to an oxide.
C)disguise the true identity of the metal.
D)prepare ultrapure metal samples.
E)enhance properties,like conductivity.

Question 6

The debris accompanying a mineral is called

A)slag.
B)gangue.
C)ore.
D)halite.
E)ash.

Question 7

The naturally occurring form of a metal that is concentrated enough to allow economical recovery of the metal is know as

A)an element.
B)a mineral.
C)gangue.
D)an ore.
E)an amalgam.

Question 8

Pyrometallurgy uses __________________ to separate a metal from its ore.

A)solid phase chemical properties
B)electrical processes
C)thermal processes
D)aqueous chemical processes
E)explosives

Question 9

Which one of these normally would not be obtained by chemical reduction?

A)Fe
B)Ti
C)Zn
D)Mg
E)Ag

Question 10

In the Hall process,____________ is reduced ____________.

A)nickel; electrolytically
B)aluminum; electrolytically
C)nickel; by reaction with metallic sodium
D)aluminum; by reaction with metallic sodium
E)copper; electrolytically

Question 11

Nickel is often purified using

A)amalgamation.
B)the Hall process.
C)the Mond process.
D)pressurization.
E)a blast furnace.

Question 12

Alloys of iron that contain 1.0-1.5% carbon and some manganese,phosphorus,silicon,and sulfur are called

A)steel.
B)cast iron.
C)coke.
D)pig iron.
E)hematite.

Question 13

Hydrometallurgy uses __________________ to separate a metal from its ore.

A)solid phase chemical properties
B)electrical processes
C)thermal processes
D)aqueous chemical processes
E)molten salt processes

Question 14

Volatile impurities are removed from ores by means of

A)roasting.
B)amalgamation.
C)electrolysis.
D)flotation.
E)zone refining.

Question 15

Which is the principal reducing agent in a blast furnace?

A)CaO(s)
B)CaSiO₃(l)
C)CO(g)
D)O₂(g)
E)CO₂(g)

Question 16

What is the source of most metals?

A)Industry
B)Synthesis
C)Saturated
D)Ocean floor
E)Minerals

Question 17

The most common source for the commercial production of sodium is called

A)sodalite.
B)limestone.
C)halite.
D)galena.
E)pyrite.

Question 18

The most common source for the commercial production of aluminum is called

A)aluminite.
B)hematite.
C)galena.
D)cinnabar.
E)bauxite.

Question 19

The flotation process used in metallurgy involves

A)the roasting of sulfides.
B)separation of gangue from ore.
C)electrolytic reduction.
D)chemical reduction of a metal.
E)zone refining.

Question 20

The process of converting metal sulfides to metal oxides is called

A)roasting.
B)smelting.
C)flotation.
D)leaching.
E)sulfoxidation.

Question 21

Cryolite,Na₃AlF₆,is used in the electrolysis of aluminum oxide because

A)it is a good source of fluoride ions.
B)it reduces the energy requirement of the process,due to its low melting point.
C)it provides a source of fluorine,an oxidizing agent.
D)it provides a source of sodium,a reducing agent.
E)it is very soluble in water.

Question 22

Which one of these elements would give a p-type semiconductor when added to a silicon crystal?

A)C
B)P
C)As
D)Ga
E)Sb

Question 23

What is the major component in milk of magnesia?

A)Mg(OH)₂
B)MgS
C)MgCl
D)MgSO₄
E)MgCO₃

Question 24

Which two compounds are produced by the Solvay process?

A)CaCO₃ and CaO
B)CaCO₃ and Na₂CO₃
C)NaHCO₃ and NaCl
D)NH₃ and NH₄Cl
E)NaHCO₃ and Na₂CO₃

Question 25

What effect does increasing temperature have on the conductivities of semiconductors?

A)Increases
B)Decreases
C)No change
D)Cannot be predicted

Question 26

The alkali metals are isolated from nonaqueous systems.Why is this necessary?

A)The electrolysis of aqueous solutions of the alkali metals requires more energy than electrolysis of the molten salts.
B)The dissolved alkali earth halides are too reactive to be electrolyzed.
C)The aqueous metal ions are more difficult to reduce than water.
D)The reduction potentials of the alkali metals are more positive than the reduction potential of water.
E)The aqueous metal ions react violently with water.

Question 27

Calcium oxide is added to molten iron in the production of carbon steel in order to

A)convert silicon and phosphorus oxides to slag which can be decanted from the molten steel.
B)serve as a scrubber to remove sulfur dioxide from the gases leaving the furnace.
C)remove any traces of acid which could weaken the steel.
D)add a small amount of oxygen to the steel to prevent corrosion and increase its strength.
E)create gangue.

Question 28

Seawater is a good source of which of the following metals?

A)Cu
B)Au
C)Mg
D)Cl
E)Ca

Question 29

According to the band theory,which of these statements provide(s)an explanation for the high electrical conductivity of metals? I.a completely filled conduction band
II)a valence band overlapping an empty conduction band
III)a filled valence band
IV)a large gap between the valence band and the conduction band

A)II
B)I and III
C)III
D)III and IV
E)IV

Question 30

What are two raw materials used in the Solvay process?

A)NaHCO₃ and NaCl
B)CaCO₃ and Na₂CO₃
C)NaCl and NaCO₃
D)NH₃ and NaCl
E)Na₂CO₃ and NH₄Cl

Question 31

According to the band theory,a band is

A)an elastic force that holds electrons close to atoms in an insulator.
B)the energy gap associated with semiconductors.
C)a large number of molecular orbitals that are close together in energy.
D)a large number of atoms in a crystal.

Question 32

Basic properties are characteristic of all alkaline earth metal oxides except one.Which is the exception?

A)BeO
B)MgO
C)SO₂
D)B₂O₃
E)CaO

Question 33

Where on the periodic table are the most reactive metals located?

A)Group IA (alkali metals)
B)Group IA (alkaline earth metals)
C)Group IIA (alkali metals)
D)Group IIA (alkaline earth metals)
E)Group VIIA (halogens)

Question 34

What is the major component in limestone?

A)NaNO₃
B)KCl
C)CaCl
D)BaSO₄
E)CaCO₃

Question 35

Which of these elements when doped into silicon would give an n-type semiconductor?

A)C
B)Ga
C)P
D)Ge
E)B

Question 36

What is the chemical formula for gypsum?

A)CaSO₄• 2H₂O
B)CaF₂
C)MgSO₄• 5H₂O
D)MgSO₄• 7H₂O
E)CaCl₂

Question 37

In the production of potassium metal,the source of electrons in the reduction of K⁺ ions is

A)H₂(g).
B)Na(g).
C)CO(g).
D)CaO(s).
E)electrolysis.

Question 38

What is the name of the relationship that exists because of the similar properties of carbon to phosphorus and nitrogen to sulfur?

A)A diagonal relationship
B)The periodic law
C)Amphoterism
D)An isoelectronic relationship
E)An allotropic relationship

Question 39

Electrolysis is used as the last step in isolating pure __________________.

A)iron
B)boron
C)aluminum
D)selenium
E)carbon

Question 40

In n-type semiconductors

A)the energy gap between the valence band and the conduction band is very large.
B)impurities that donate electrons are added to provide conduction electrons.
C)a valence band overlaps the empty conduction band.
D)impurities that provide "positive holes" are added to a pure semiconductor.

Question 41

Which of these ions is most likely to substitute for Ca²⁺ in the human body?

A)Cl^-
B)Sr²⁺
C)K⁺
D)S^2-
E)Pb²⁺

Question 42

The mineral cryolite,Na₃AlF₆,is used in the Hall process for aluminum production as

A)the source of aluminum (the ore).
B)a chemical reducing agent.
C)a material that forms a slag and thus removes impurities.
D)a solvent for alumina,Al₂O₃.

Question 43

In the production of aluminum,bauxite is heated with sodium hydroxide solution to _____.

A)remove titanium(IV)oxide
B)remove silica
C)remove iron oxides
D)remove potassium
E)remove fluorides

Question 44

Which mineral is not a carbonate?

A)Witherite
B)Sylvite
C)Smithsonite
D)Cerussite
E)Calcite

Question 45

In gunpowder,which component is present in the highest percent by mass?

A)Wood charcoal
B)Chile salt peter
C)Potassium nitrate
D)Sulfur
E)Ammonia

Question 46

Which reaction is a good small-scale laboratory method for the preparation of hydrogen?

A)CH₄(g)+ H₂O(g)→ CO(g)+ 3H₂(g)
B)3FeCl₂ (s)+ 4H₂O(g)→ Fe₃O₄(s)+ 6HCl(g)+ H₂(g)
C)NaH(s)+ H₂O(l)→ NaOH(aq)+ H₂(g)
D)CO(g)+ H₂O(g)→ CO₂(g)+ H₂(g)
E)None of these methods is useful.

Question 47

The Downs cell is used in the production of

A)copper.
B)hydrogen.
C)iron.
D)magnesium.
E)sodium.

Question 48

What is the molecular shape of AlF₃?

A)Tetrahedral
B)Linear
C)Trigonal pyramidal
D)Square planar
E)Trigonal planar

Question 49

The Hall process involves the reduction of Al₂O₃ to aluminum by

A)carbon (coke).
B)carbon monoxide.
C)molecular hydrogen.
D)sodium.
E)electrolysis.

Question 50

Which is an example of a basic oxide?

A)SO₃(g)
B)BaO(s)
C)Al₂O₃(s)
D)Fe₂O₃(s)
E)SiO₂(s)

Question 51

Magnesium reacts with dilute hydrochloric acid according to which of these equations?

A)Mg + 2HCl → 2H⁺ + MgCl
B)Mg + 2HCl → H₂ + MgCl₂
C)Mg + 2HCl → Cl₂ + MgH₂
D)Mg + 2HCl → Cl₂ + Mg²⁺ + 2H⁺

Question 52

The final step of the purification of copper involves electrorefining in which copper is separated from nickel and iron by being reduced at the cathode of a cell.Why are nickel and iron not reduced?

A)Their reduction potentials are more positive than copper's.
B)Their reduction potentials are more negative than copper's.
C)They cannot be deposited on a copper electrode.
D)Their reduction potentials are more negative than water's.
E)Their reduction requires large overvoltages.

Question 53

The process used to produce metals with a purity of more than 99.99% is called

A)zone refining.
B)electrorefining.
C)distillation.
D)sublimation.
E)alloying.

Question 54

Aluminum is an active metal,but does not corrode as iron does because

A)Al does not react with O₂ .
B)a protective layer of Al₂O₃ forms on the metal surface.
C)Al is harder to oxidize than is Fe.
D)the enthalpy of formation of aluminum oxide is negative.
E)aluminum has a high tensile strength.

Question 55

_____ consists of potassium nitrate,wood charcoal,and sulfur.

A)Salt peter
B)Chile salt peter
C)Carborundum
D)Gunpowder
E)Anglesite

Question 56

Which metal's commercial source is seawater?

A)Cs
B)K
C)Mg
D)Ba
E)Li

Question 57

Which is a covalent oxide?

A)CaO
B)Na₂O
C)Li₂O
D)Cs₂O
E)BeO

Question 58

The Hall process refers to

A)the production of aluminum by electrolysis.
B)the recovery of sulfur from underground deposits.
C)the manufacture of sulfuric acid.
D)the production of ammonia from nitrogen and hydrogen gases.
E)the isolation of Al₂O₃ from bauxite.

Question 59

Which undergoes electrolysis to form calcium metal?

A)Ca(OH)₂
B)Ca(NO₃)₂
C)CaI₂
D)CaF₂
E)CaCl₂

Question 60

Which statement is not correct?

A)Aluminum has a low density versus other metals.
B)Al(OH)₃ is an amphoteric compound.
C)Metallic aluminum is toxic to humans.
D)Aluminum is very reactive with oxygen.
E)Metallic aluminum conducts electricity.

Question 61

Which mineral is not a silicate?

A)Zircon
B)Beryl
C)Smithsonite
D)Albite
E)Talc

Question 62

Group 1A elements are called alkaline earth metals.

Question 63

Which mineral contains calcium as a major element?

A)Cinnabar
B)Corundum
C)Hematite
D)Hydroxyapatite
E)Talc

Question 64

What is the chemical formula for phosphate rock?

A)Na₃PO₄
B)Na₃P
C)Mg₃(PO₄)₂
D)AlPO₄
E)Ca₃(PO₄)₂

Question 65

What is the name of the process used to separate the minerals from the waste in ore?

A)Gangue
B)Mining
C)Fetching
D)Flotation
E)Mineral drawing

Question 66

Which diagram best corresponds to the energy level diagram of a semiconductor?

A)
B)
C)
D)
E)

Question 67

Which ion is not found in sea water in a concentration high enough to be an industrial source of the metal?

A)Ca²⁺
B)Mg²⁺
C)Na⁺
D)K⁺
E)Ag⁺

Question 68

What is the chemical formula for cinnabar?

A)HgS
B)SnBr
C)SnO₂
D)TiO₂
E)SnBr₄

Question 69

Which mineral is a silicate?

A)Cinnabar
B)Corundum
C)Smithsonite
D)Hydroxyapatite
E)Talc

Question 70

The following electrolytic cell is a representation of the process used to purify copper metal.How does it work? .

A)Impure copper is oxidized at the anode,and pure copper is reduced at the cathode.Impurities dissolve into solution.
B)Impure copper is oxidized at the cathode,and pure copper is reduced at the anode.Impurities dissolve into solution.
C)Impure copper is oxidized at the anode,and pure copper dissolves into solution.Impurities remain on the cathode.
D)Impure copper is oxidized at the cathode,and pure copper dissolves into solution.Impurities remain on the anode.
E)Impure copper precipitates from solution onto the cathode,and pure copper remains on the anode.

Question 71

What is the chemical formula for talc?

A)NaNO₃
B)Mg₃(PO₄)₂
C)CaCO₃
D)Mg₃(Si₄O₁₀)(OH)₂
E)Ca₃(PO₄)₂

Question 72

What type of metal is generally separated using a strong electromagnet?

A)ferromagnetic
B)oxide
C)alkaline
D)uncombined

Question 73

What is the chemical formula for limestone?

A)LiOH
B)Li₂CO₃
C)CaCO₃
D)BaCO₃
E)Ca₃(PO₄)₂

Question 74

Which diagram best corresponds to the energy level diagram of a metal?

A)
B)
C)
D)

Question 75

A fractional distillation method called the Mond process is used to purify nickel.

Question 76

The first step in the purification of a metal M is represented by the following figure.To which process does the figure correspond,and which metal is usually purified by this process?

A)The Mond process,for the purification of Zn
B)The Mond process,for the purification of Ni
C)The Hall process,for the purification of Al
D)The Hall process,for the purification of Cr
E)The zone refining process,for the purification of Fe

Question 77

Which is NOT a chemical reaction that occurs in a blast furnace in the production of iron?

A)CaCO₃(s)→ CaO(s)+ CO₂(g)
B)3Fe₂O₃(s)+ CO(g)→ 2Fe₃O₄(s)+ CO₂(g)
C)2FeO(s)+ CO(g)→ Fe₂O₃(s)+ C(s)
D)Fe₃O₄(s)+ CO(g)→ 3FeO(s)+ CO₂(g)
E)FeO(s)+ CO(g)→ Fe(l)+ CO₂(g)

Question 78

Which is the best representation for a solution composed of sodium dissolved in liquid ammonia? (Ammonia molecules have been omitted for clarity.)

A)
B)
C)
D)
E)

Question 79

For the production of metallic chromium at high temperatures,which is NOT an appropriate choice for the metal M? Cr₂O₃(s)+ 3M(l)→ 2Cr(l)+ 3MO(s)

A)Mg
B)Sn
C)Ca
D)Cu
E)Sr

Question 80

When mercury combines with other metals,what is the name given to the species formed?

A)Mercury complex
B)Mercury poison
C)Amalgam
D)Mineralization
E)Mercuration