Deck 21: Metals and Solid-State Materials

Question 1

Which of the following metals occurs in nature principally as oxide ores?

A)Ca
B)Co
C)Cr
D)Cu

Answer 1

Cr

Question 2

Which of the following elements is most likely to occur as a metal sulfide ore?

A)Hf
B)Hg
C)K
D)W

Answer 2

Hg

Question 3

Which metal is not found in nature in uncombined form?

A)Ag
B)Au
C)Pd
D)Pt

Answer 3

Ag

Question 4

What metal is isolated from the ore galena?

A)lead
B)manganese
C)tin
D)zinc

Question 5

Which of the following steps is not always necessary in the extraction of a metal from its ore?

A)chemical treatment prior to reduction
B)concentration of the ore
C)reduction of the mineral to the free metal
D)refining or purification of the metal

Question 6

Vanadium ore contains two isotopes of vanadium,⁵⁰V and ⁵¹V.The least abundant isotope is radioactive and undergoes beta capture.What is the product of the beta decay?

A)(⁵⁰Cr)
B)(⁵¹Cr)
C)(⁵⁰Ti)
D)(⁵¹Ti)

Question 7

What is a principal commercial ore for the element iron?

A)cassiterite
B)cinnabar
C)galena
D)hematite

Question 8

What is a principal commercial ore for the element aluminum?

A)bauxite
B)chalcopyrite
C)chromite
D)hematite

Question 9

Which substance is commonly found in nature in an uncombined form?

A)aluminum
B)iron
C)platinum
D)tin

Question 10

What are the most abundant minerals in the earth's crust?

A)aluminosilicates and silicates
B)chlorides and iodides
C)nitrates and phosphates
D)oxides and sulfides

Question 11

What is not a metallurgy process?

A)environmental reconstruction of the landscape
B)extraction of metals from their ores
C)making of alloys and metallic composites
D)reduction of the mineral to the free metal

Question 12

What statement is inconsistent concerning the correlation of the chemical compositions of the most common ores with the locations of their metals in the periodic table?

A)Gold and the platinum-group metals (Ru,Os,Rh,Ir,Pd,and Pt)are sufficiently unreactive to occur commonly as the free metals.
B)The early transition metals on the left side of the d block generally occur as oxides while the more electronegative,late transition metals on the right side of the d block occur as sulfides.
C)The more electronegative p-block metals are commonly found as oxides and nitrates except for Al and Sn which are found as sulfides.
D)The s-block metals are found in nature as carbonates,silicates and in the case of Na and K as chlorides.

Question 13

What minerals are important commercial sources of metals?

A)aluminosilicates and silicates
B)chlorides and iodides
C)nitrates and phosphates
D)oxides and sulfides

Question 14

What metal is isolated from the ore sphalerite?

A)copper
B)manganese
C)titanium
D)zinc

Question 15

Limnite is an ore having a formula that is sometimes written as an iron(III)oxide hydrate,Fe₂O₃·xH₂O.If 1.00 kg of limnite produces 0.747 kg of anhydrous Fe₂O₃ upon heating,what is the number of waters of hydration x in the Fe₂O₃·xH₂O?

A)1
B)2
C)3
D)4

Question 16

What metal is isolated from the ore rutile and what is the chemical formula of rutile?

A)aluminum,Al₂O₃ ∙ xH₂O
B)manganese,MnO₂
C)tin,SnO₂
D)titanium,TiO₂

Question 17

What is the concentration process used to separate chalcopyrite (CuFeS₂)from its gangue?

A)chemical treatment
B)density differences
C)floatation process
D)magnetic differences

Question 18

Which of the following elements is most likely to naturally occur as a carbonate?

A)Ca
B)Co
C)Cr
D)Cu

Question 19

Which oxide ore will yield the greatest number of grams of pure metal per kilogram of ore?

A)cassiterite,SnO₂
B)hematite,Fe₂O₃
C)pyrolusite,MnO₂
D)rutile,TiO₂

Question 20

What is the most important copper containing ore?

A)cassitrite
B)chalcopyrite
C)chromite
D)cinnabar

Question 21

What is not a major component of slag?

A)CaSiO₃
B)Ca₃(PO₄)₂
C)Fe₂O₃
D)MnSiO₃

Question 22

To three significant figures,how many metric tons of iron ore are needed to produce 10,000 metric tons of iron per day in the blast furnace process? Assume that the iron ore is iron(III)oxide and that the ore is 70.0% pure.The reaction of interest is Fe₂O₃(s)+ 3 CO(g)→ 2 Fe(l)+ 3 CO₂(g).

A)14,300 metric tons
B)20,000 metric tons
C)20,400 metric tons
D)30,000 metric tons

Question 23

What is not a primary ingredient used in the production of iron by the blast furnace process?

A)coke
B)iron ore
C)limestone
D)phosphates and silicates

Question 24

What is the name of the process commonly associated with the isolation and concentration of Al₂O₃ from the ore bauxite (Al₂O₃ ∙ xH₂O)?

A)basic oxygen process
B)bayer process
C)contact process
D)mond process

Question 25

How is slag separated from molten ore in a blast furnace?

A)chemical treatment
B)density differences
C)distillation
D)magnetic differences

Question 26

Why is silicon dioxide added to molten iron in the basic oxygen process?

A)to remove acidic oxides from the molten iron
B)to remove manganese oxide from the molten iron
C)to remove phosphates and carbonates from the molten iron
D)to remove trace amounts of carbon from the molten iron

Question 27

Zinc occurs in sulfide ores.How many liters of SO₂(g)are produced at STP for each kilogram of roasted ore that is 70% zinc sulfide?

A)160 L
B)230 L
C)460 L
D)660 L

Question 28

Which element is likely to be a principal impurity in zinc ore?

A)cadmium
B)copper
C)gallium
D)nickel

Question 29

Steel is a mixture composed primarily of ________.

A)iron and carbon
B)iron and copper
C)iron and silicon
D)iron and sulfur

Question 30

When zinc sulfide undergoes roasting,the products are

A)Zn and S
B)Zn and H₂S
C)ZnO and S
D)ZnO and SO₂

Question 31

Why is CaCO₃ added to a blast furnace in the steel making process?

A)to give a source of CO₂
B)to remove basic oxides from the iron ore
C)to remove silicates and phosphates from the iron ore
D)to remove unreactive carbon from the iron ore

Question 32

What is not an appropriate method of isolating the metals shown?

A)HgS(s)+ O₂(g)+ heat → Hg(g)+ SO₂(g)
B)ZnO(s)+ C(s)+ heat → Zn(g)+ CO(g)
C)WO₃(s)+ 3 H₂(g)+ heat → W(s)+ 3 H₂O(g)
D)Al₂O₃(s)+ 2 Cr(s)+ heat → Cr₂O₃(s)+ 2 Al(l)

Question 33

How does one commercially reduce the metal oxides or chlorides of sodium and magnesium?

A)electrolysis of the molten salts
B)high temperature reduction with aluminum
C)high temperature reduction with carbon
D)roasting

Question 34

What is the chemical process most likely to be used to purify nickel metal?

A)distillation
B)electrorefining
C)reaction with carbon monoxide (a Mond process)
D)reaction with iodine

Question 35

In the reaction shown below calcium phosphate slag is formed from a reaction of calcium oxide with phosphoric anhydride.
6 CaO(s)+ P₄O₁₀(l)→ 2 Ca₃(PO₄)₂(l)
CaO is a(n)________ oxide,and P₄O₁₀ is a(n)________ oxide.

A)acidic,acidic
B)acidic,basic
C)basic,acidic
D)basic,basic

Question 36

What terminology best describes the bonding in the following schematic of a metal?

A)ionic bonding
B)covalent bonding
C)electron-sea model
D)crystal model

Question 37

What conditions favor the decomposition of Ni(CO)₄ into Ni and CO after equilibrium is established in the reaction Ni(s)+ 4 CO(g)⇌ Ni(CO)₄(g)that has both ΔH and ΔS being negative?

A)decrease volume
B)increase pressure
C)increase temperature
D)simultaneously increase the pressure and decrease volume

Question 38

Which of the following metals is not commonly obtained by electrolysis?

A)Al
B)Li
C)Na
D)Zn

Question 39

What is the chemical process most likely to be used to purify zirconium metal?

A)distillation
B)electrorefining
C)reaction with carbon monoxide (a Mond process)
D)reaction with iodine

Question 40

The chemical process of roasting is commonly used to facilitate the reduction of which metal ores?

A)Ag,Cu,and Hg
B)Al,Mg,and Na
C)Au and Pt
D)Fe,Mn,and V

Question 41

How would one classify copper mixed with tin?

A)conductor
B)n-type semiconductor
C)p-type semiconductor
D)insulator

Question 42

Which element has the smallest energy band gap?

A)C (diamond)
B)Ge
C)Pb
D)Si

Question 43

What type of substances exhibit an increase in conductivity with an increase in temperature?

A)both metals and semiconductors
B)only insulators
C)only metals
D)only semiconductors

Question 44

Electrical resistance of a metal ________ with increasing temperature.

A)can decrease or increase
B)decreases
C)does not change
D)increases

Question 45

How would one classify a silicon crystal doped with indium?

A)conductor
B)n-type semiconductor
C)p-type semiconductor
D)insulator

Question 46

According to band theory,which one of the following metals is expected to have the highest melting point?

A)Cd
B)Cr
C)Hg
D)Zn

Question 47

Which one of the following is an n-type of semiconductor?

A)alumina
B)germanium doped with antimony
C)germanium doped with boron
D)tellurium

Question 48

A light emitting diode with a band gap of 181 kJ/mol emits light in what region of the electromagnetic radiation spectrum?

A)infrared
B)ultraviolet
C)visible - blue
D)visible - red

Question 49

Which substance is a good semiconductor?

A)diamond
B)germanium
C)gold
D)phosphorus

Question 50

Which metal has maximum filling of bonding molecular orbitals and minimal filling of antibonding molecular orbitals in its composite s-d band?

A)Au
B)Cs
C)Re
D)W

Question 51

White tin has an electrical conductivity that decreases with increasing temperature,and gray tin has an electrical conductivity that increases with increasing temperature.Therefore,white tin is classified as a(n)________,and gray tin is classified as a(n)________.

A)insulator,metal
B)metal,insulator
C)metal,semiconductor
D)semiconductor,metal

Question 52

Which element has the largest energy band gap?

A)C (diamond)
B)Si
C)Ge
D)Sn (white)

Question 53

Which substance has a larger band gap than silicon?

A)diamond
B)copper
C)germanium
D)silver

Question 54

How would one classify a germanium crystal doped with arsenic?

A)conductor
B)n-type semiconductor
C)p-type semiconductor
D)insulator

Question 55

According to band theory,which of the following metals is expected to have the strongest bonding and highest melting point?

A)Cs
B)Cu
C)Rb
D)Ru

Question 56

Which one of the following is an electrical insulator?

A)alumina
B)germanium doped with antimony
C)gold
D)tellurium

Question 57

Which of the following is a semiconductor?

A)Al
B)B
C)Ga
D)Pb

Question 58

Which combination of semiconductors can be employed to make a diode?

A)GaAs doped with Ge and GaP doped with Si
B)GaAs doped with Se and GaP doped with Zn
C)Si doped with B and Ge doped with Ga
D)Si doped with P and Ge doped with As

Question 59

Which one of the following is a p-type of semiconductor?

A)germanium doped with antimony
B)germanium doped with boron
C)tellurium
D)YBa₂Cu₃O₇

Question 60

Which substance is the best conductor of electricity?

A)diamond
B)germanium
C)gold
D)phosphorus

Question 61

What is not generally considered to be a ceramic?

A)indium,In
B)silica,SiO₂
C)silicon nitride,Si₃N₄
D)zirconia,ZiO₂

Question 62

A particular superconductor has eight copper atoms on corners and eight copper atoms on edges of its unit cell.How many copper atoms are attributed to a single unit cell of this superconductor?

A)1
B)3
C)5
D)16

Question 63

Which process is used in the fabrication of ceramics?

A)electrolysis
B)reduction
C)roasting
D)sintering

Question 64

Why are ceramics so much more brittle than metals?

A)The bonding in ceramics has a very high degree of ionic bonding character.
B)The bonding in ceramics has a very high degree of pi bonding character.
C)The bonding in ceramics is highly nondirectional.
D)The localized bonding in ceramics is highly directional.

Question 65

What is the Meissner effect associated with superconductors? It is ________.

A)when the temperature above which the superconductor fails to work
B)when the temperature at which the superconductors become perfect insulators
C)when the net magnetic field within the bulk of the superconductor is zero
D)when the net magnetic field within the bulk of the superconductor becomes nearly infinite

Question 66

Which one of the following is a metallic conductor at room temperature but a superconductor at 18 K?

A)diamond
B)graphite
C)fullerene
D)potassium fulleride

Question 67

What is the sol-gel process?

A)a series of chemical steps that involves the isolation of CuS and then roasting with oxygen
B)a series of chemical steps that involves the isolation of SO₃ and then treatment with H₂SO₄
C)a series of chemical steps that involves the synthesis of a metal oxide powder from a metal alkoxide
D)a series of chemical steps that involves the thermal decomposition of fibers of polyacrylonitrile

Question 68

What is not part of the sol-gel process for the production of titania?

A)TiCl₄ + 4 HOCH₂CH₃ + 4 NH₃ → Ti(OCH₂CH₃)₄ + 4 NH₄Cl (in benzene)
B)Ti(OCH₂CH₃)₄ + 4 H₂O → Ti(OH)₄ + 4 HOCH₂CH₃
C)(HO)₃-Ti-OH + HO-Ti-(OH)₃ → (HO)₃-Ti-O-Ti(OH)₃ + H₂O
D)4 Ti(OH)₄ + heat → 2 Ti₂O₃ + 8 H₂O + O₂

Question 69

Below the superconducting transition temperature T_c,superconductors ________.

A)become perfect conductors
B)become perfect magnets
C)become perfect resistors
D)fail to work

Question 70

Sintering is

A)a filtration process through a molecular sieve.
B)the process of heating particles of a powder below the melting point so that they fuse together.
C)the process of rapid cooling of a material to yield a superconducting mixture.
D)the process of removing metals from ore by passing material through a magnetic field.

Question 71

Who discovered the phenomenon of superconductivity in 1911?

A)J)G.Bednorz
B)R)B.Fuller
C)K)A.M ller
D)H)K.Onnes

Question 72

What structural features appear necessary for superconductivity in the 1-2-3 YBa₂Cu₃O₇ superconductor?

A)high metallic character
B)infinite extended layers of Cu and O atoms and a fractional oxidation state for Cu
C)presence of an inner transition element
D)All of these are necessary.

Question 73

What substance has a rating of 10 on the Mohs hardness scale?

A)alumina
B)aluminum
C)diamond
D)talc

Question 74

What is the average oxidation state of Cu in HgCa₂Ba₂Cu₃O_8-x if Hg is in the +2 oxidation state?

A)+1
B)+2
C)+2 - 2x/3
D)+2 + 2x/3

Question 75

Which has been found to be a three dimensional superconductor that conducts equally in all directions?

A)C (diamond)
B)C (graphite)
C)K₃C₆₀
D)YBa₂Cu₃O₇

Question 76

Why are ceramics superior to metals as structural materials?

A)Ceramics are easier to fabricate into shapes than metals.
B)Ceramics are more malleable than metals.
C)Ceramics are more resistant to wear and corrosion than metals.
D)Ceramics have greater impact resistance than metals.

Question 77

What is the name of the oxide ceramic BeO?

A)beryllia
B)beryllic
C)beryllium ceramic
D)beryllium oxide

Question 78

What is the coordination number of Si in SiC that has a diamond-like structure?

A)1
B)2
C)4
D)6

Question 79

What is the average oxidation number of Cu in the 1-2-3 superconductor YBa₂Cu₃O₇ if Y is in the +3 oxidation state?

A)+2
B)+2.33
C)+3
D)+3.33

Question 80

What element was found to be the first superconductor of electricity at 4.2 K in 1911?

A)copper
B)iron
C)gallium
D)mercury