Question 1

Which one of these metals would normally be obtained by chemical reduction

Accepted Answer

A)   aluminum
B)   calcium
C)   lithium
D)   sodium
E)   vanadiumF) None of the above
G) B) and C)

Question 2

Volatile impurities are removed from ores by means of

Accepted Answer

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

Question 3

What is the total number of moles (n)  of electrons exchanged between the oxidizing agent and the reducing agent in the reaction below to obtain vanadium metal
V2O5(s)  + 5Ca(l)   →\rarr→  2V(l)  + 5CaO(s)

Accepted Answer

A)   1
B)   2
C)   5
D)   10
E)   0 F) A) and C)
G) A) and B)

Question 4

Cryolite, Na3AlF6, is mixed with alumina prior to electrolysis in the production of Al because it acts a solute.

Accepted Answer

A) True 
 B)False

Question 5

The equilibrium 3Fe(s)  + C(s)   →\rarr→ Fe3C(s)  is established in a solid solution. For such a solution, one can write an equilibrium constant expression in the usual way except that the concentrations that refer to solids in the solid solution are included. Determine the equilibrium constant for the formation of cementite from iron and carbon at 680 ∘\circ∘ C. (Given: for this reaction at 25 ∘\circ∘ C,  Δ\DeltaΔ H ∘\circ∘ = 21 kJ/mol and  Δ\DeltaΔ S ∘\circ∘  = 20.4 J/mol.K)

Accepted Answer

A)   0.75
B)   0.33
C)   3.1
D)   0.82
E)   1.2 F) D) and E)
G) B) and E)

Question 6

In the Mond process, nickel is purified by

Accepted Answer

A)   dissolving the crude ore in sulfuric acid, and precipitating the nickel(II)  ion as the sulfate salt.
B)   dissolving the crude ore in a lye (NaOH)  solution, and precipitating the nickel(II)  ion as the hydroxide salt.
C)   heating the crude ore to its melting point and electrolytically reducing the nickel(II)  ions to form the metal.
D)   passing sodium gas over the crude ore at high temperatures, chemically reducing the nickel(II)  to nickel metal.
E)   passing carbon monoxide over the impure metal at high temperature, forming the volatile Ni(CO) 4 which is removed as a gas.F) None of the above
G) A) and C)

Question 7

The following reaction is used to produce titanium metal at high temperature.TiCl4(g)  + 2Mg(l)   →\rarr→  Ti(s)  + 2MgCl2(l)  
Which element is oxidized and which is reduced

Accepted Answer

A)   Both titanium and magnesium are oxidized
B)   Titanium is reduced, magnesium is oxidized
C)   Magnesium is reduced, titanium is oxidized
D)   Neither titanium or magnesium is oxidized
E)   None of the above F) A) and B)
G) A) and C)

Question 8

What effect does increasing temperature have on the conductivities of semiconductors

Accepted Answer

A)   increases
B)   decreases
C)   no change
D)   cannot be predictedE) B) and C)
F) All of the above

Question 9

Which of the following diagrams represents a semiconductor

Accepted Answer

A)   A
B)   B
C)   CD) All of the above
E) None of the above

Question 10

Bauxite (Al2O3$\times$2H2O) ore is the principal commercial source of aluminum metal.

Accepted Answer

A) True 
 B)False

Question 11

Mercury, magnesium, and zinc have low enough boiling points that they can be purified by distillation.

Accepted Answer

A) True 
 B)False

Question 12

Aluminum hydroxide, Al(OH) 3, is

Accepted Answer

A)   an acid.
B)   an amphoteric hydroxide.
C)   a base.
D)   an explosive hydroxide.
E)   used to make amalgams.F) B) and D)
G) None of the above

Question 13

The principal reducing agent in a blast furnace is

Accepted Answer

A)   CaO(s) 
B)   CaSiO3(l) 
C)   CO(g) 
D)   O2(g) 
E)   CO2(g) F) None of the above
G) A) and B)

Question 14

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

Accepted Answer

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

Question 15

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

Accepted Answer

A)   C
B)   Ga
C)   P
D)   Ge
E)   BF) B) and E)
G) None of the above

Question 16

A naturally occurring substance with a range of chemical composition is

Accepted Answer

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

Question 17

According to the band theory, which of these statements provide(s)  an explanation for the high electrical conductivity of metals
I. a partly 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

Accepted Answer

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

Question 18

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

Accepted Answer

A)   C
B)   P
C)   As
D)   Ga
E)   SbF) A) and D)
G) B) and D)

Question 19

Write the chemical formula of epsomite (sold in pharmacies as Epsom salts) .

Accepted Answer

A)   CaSO4 ×	imes× 7H2O
B)   MgSO4 ×	imes× 7H2O
C)   Na2SO4 ×	imes× 7H2O
D)   FeSO4 ×	imes× 7H2O
E)   None of the above F) None of the above
G) A) and C)

Question 20

Which one of these elements has seawater as its commercial source

Accepted Answer

A)   Mg
B)   Al
C)   Ca
D)   Sn
E)   CdF) A) and E)
G) D) and E)

Exam 21: Metallurgy and the Chemistry of Metals

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

Correct Answer
verified

Which one of these elements has seawater as its commercial source

Correct Answer
verified

Cryolite, Na₃AlF₆, is mixed with alumina prior to electrolysis in the production of Al because it acts a solute.

Correct Answer
verified

A naturally occurring substance with a range of chemical composition is

Correct Answer
verified

In the Mond process, nickel is purified by

Correct Answer
verified

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

Correct Answer
verified

Which of the following diagrams represents a semiconductor

Correct Answer
verified

The following reaction is used to produce titanium metal at high temperature.TiCl₄(g) + 2Mg(l) $\rarr$ Ti(s) + 2MgCl₂(l) Which element is oxidized and which is reduced

Correct Answer
verified

What is the total number of moles (n) of electrons exchanged between the oxidizing agent and the reducing agent in the reaction below to obtain vanadium metal V₂O₅(s) + 5Ca(l) $\rarr$ 2V(l) + 5CaO(s)

Correct Answer
verified

Correct Answer
verified

Write the chemical formula of epsomite (sold in pharmacies as Epsom salts) .

Correct Answer
verified

What effect does increasing temperature have on the conductivities of semiconductors

Correct Answer
verified

Bauxite (Al₂O₃ $\times$ 2H₂O) ore is the principal commercial source of aluminum metal.

Correct Answer
verified

Which one of these metals would normally be obtained by chemical reduction

Correct Answer
verified

Correct Answer
verified

The principal reducing agent in a blast furnace is

Correct Answer
verified

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

Correct Answer
verified

Volatile impurities are removed from ores by means of

Correct Answer
verified

Aluminum hydroxide, Al(OH) ₃, is

Correct Answer
verified

Mercury, magnesium, and zinc have low enough boiling points that they can be purified by distillation.

Correct Answer
verified

Exam 21: Metallurgy and the Chemistry of Metals

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

Correct AnswerverifiedShow Answer

Which one of these elements has seawater as its commercial source

Correct AnswerverifiedShow Answer

Cryolite, Na3AlF6, is mixed with alumina prior to electrolysis in the production of Al because it acts a solute.

Correct AnswerverifiedShow Answer

A naturally occurring substance with a range of chemical composition is

Correct AnswerverifiedShow Answer

In the Mond process, nickel is purified by

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Which of the following diagrams represents a semiconductor

Correct AnswerverifiedShow Answer

The following reaction is used to produce titanium metal at high temperature.TiCl4(g) + 2Mg(l) →\rarr→ Ti(s) + 2MgCl2(l) Which element is oxidized and which is reduced

Correct AnswerverifiedShow Answer

What is the total number of moles (n) of electrons exchanged between the oxidizing agent and the reducing agent in the reaction below to obtain vanadium metal V2O5(s) + 5Ca(l) →\rarr→ 2V(l) + 5CaO(s)

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Write the chemical formula of epsomite (sold in pharmacies as Epsom salts) .

Correct AnswerverifiedShow Answer

What effect does increasing temperature have on the conductivities of semiconductors

Correct AnswerverifiedShow Answer

Bauxite (Al2O3 ×\times× 2H2O) ore is the principal commercial source of aluminum metal.

Correct AnswerverifiedShow Answer

Which one of these metals would normally be obtained by chemical reduction

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The principal reducing agent in a blast furnace is

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Volatile impurities are removed from ores by means of

Correct AnswerverifiedShow Answer

Aluminum hydroxide, Al(OH) 3, is

Correct AnswerverifiedShow Answer

Mercury, magnesium, and zinc have low enough boiling points that they can be purified by distillation.

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Cryolite, Na₃AlF₆, is mixed with alumina prior to electrolysis in the production of Al because it acts a solute.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The following reaction is used to produce titanium metal at high temperature.TiCl₄(g) + 2Mg(l) $\rarr$ Ti(s) + 2MgCl₂(l) Which element is oxidized and which is reduced

Correct Answer
verified

What is the total number of moles (n) of electrons exchanged between the oxidizing agent and the reducing agent in the reaction below to obtain vanadium metal V₂O₅(s) + 5Ca(l) $\rarr$ 2V(l) + 5CaO(s)

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Bauxite (Al₂O₃ $\times$ 2H₂O) ore is the principal commercial source of aluminum metal.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Aluminum hydroxide, Al(OH) ₃, is

Correct Answer
verified

Correct Answer
verified