Question 1

In the industrial electrolysis of aqueous NaCl (the chlor-alkali process), the modern trend is toward the use of cells incorporating polymer membranes to separate the anode and cathode solutions.

Accepted Answer

A) True 
 B)False

Question 2

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

Accepted Answer

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.F) C) and E)
G) A) and E)

Question 3

What gas is produced at the anode in the Downs cell, in which molten NaCl is electrolyzed?

Accepted Answer

The answer of What gas is produced at the anode...

Question 4

The Earth's core consists mainly of:

Accepted Answer

A)   Ni
B)   O
C)   Al
D)   Si
E)   FeF) D) and E)
G) B) and E)

Question 5

What are the main mineral sources of phosphorus?

Accepted Answer

A)   phosphides
B)   phosphites
C)   phosphors
D)   phosphates
E)   elemental phosphorusF) B) and E)
G) C) and D)

Question 6

Hydrometallurgy uses __________________ to separate a metal from its ore.

Accepted Answer

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

Question 7

The leaching of gold can be represented by the equation  In this reaction, identify the oxidant, the reductant and the oxidation numbers of the elements which change.

Accepted Answer

The oxidant is O₂, the reductan...

Question 8

The ______________ process uses a boiling 30% sodium hydroxide solution to treat bauxite.

Accepted Answer

A)   Bayer
B)   Hall-Héroult
C)   Dow
D)   Frasch
E)   HaberF) A) and B)
G) A) and C)

Question 9

Aluminum and magnesium form are light metals which are used in many structural applications. Although they are highly active metals (as their electrode potentials suggest), they can often be used without the use of paint or other applied finishes to protect them against corrosion. How is this possible?

Accepted Answer

Both Al and Mg have strong, adherent, re...

Question 10

Pyrometallurgy uses __________________ to separate a metal from its ore.

Accepted Answer

A)   solid phase chemical properties
B)   electrical processes
C)   thermal processes
D)   aqueous chemical processes
E)   explosivesF) B) and C)
G) B) and D)

Question 11

The atmosphere contains about 700. billion metric tons of carbon in the form of carbon dioxide. In the carbon cycle, about 200. billion metric tons of carbon (as carbon dioxide)  enters the atmosphere each year. Assuming that 200. billion metric tons of carbon also leaves the atmosphere annually, how many years does the average carbon atom spend in the atmosphere in each cycle?

Accepted Answer

A)   0.29 years
B)   3.5 years
C)   500. years
D)   140,000 years
E)   More information is needed in order to calculate the answer.F) A) and B)
G) None of the above

Question 12

The most common source for commercial production of sodium is called

Accepted Answer

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

Question 13

Sulfur trioxide is the anhydride of sulfuric acid. However, SO3 is not added directly to water during the synthesis of sulfuric acid because

Accepted Answer

A)   hydration of SO3 is very exothermic and difficult to control.
B)   hydration of SO3 is very endothermic and proceeds too slowly to be profitable.
C)   at high temperatures, water vapor catalyzes polymerization of SO3.
D)   vapor phase sulfuric acid is corrosive and limits the useful life of the reactor.
E)   the water would decompose under such conditions.F) All of the above
G) B) and E)

Question 14

Which one of the following species or compounds reacts at the cathode in the Hall-Héroult process?

Accepted Answer

A)   Al2O3
B)   Al(OH) 3
C)   F¯
D)   AlF63¯
E)   CF) All of the above
G) A) and E)

Question 15

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

Accepted Answer

A)   iron
B)   boron
C)   aluminum
D)   selenium
E)   carbonF) B) and E)
G) B) and C)

Question 16

What gas is produced during the Hall-Héroult process for production of aluminum?

Accepted Answer

A)   chlorine, Cl2
B)   oxygen, O2
C)   hydrogen, H2
D)   ammonia, NH3
E)   carbon dioxide, CO2F) A) and B)
G) C) and E)

Exam 22: The Elements in Nature and Industry

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

Correct Answer
verified

The Earth's core consists mainly of:

Correct Answer
verified

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

Correct Answer
verified

The ______________ process uses a boiling 30% sodium hydroxide solution to treat bauxite.

Correct Answer
verified

Correct Answer
verified

The most common source for commercial production of sodium is called

Correct Answer
verified

What gas is produced at the anode in the Downs cell, in which molten NaCl is electrolyzed?

Correct Answer
verified

Hydrometallurgy uses __________________ to separate a metal from its ore.

Correct Answer
verified

The leaching of gold can be represented by the equation In this reaction, identify the oxidant, the reductant and the oxidation numbers of the elements which change.

Correct Answer
verified
The oxidant is O₂, the reductan...
View Answer

Correct Answer
verified
Both Al and Mg have strong, adherent, re...
View Answer

Pyrometallurgy uses __________________ to separate a metal from its ore.

Correct Answer
verified

Sulfur trioxide is the anhydride of sulfuric acid. However, SO₃ is not added directly to water during the synthesis of sulfuric acid because

Correct Answer
verified

Which one of the following species or compounds reacts at the cathode in the Hall-Héroult process?

Correct Answer
verified

What gas is produced during the Hall-Héroult process for production of aluminum?

Correct Answer
verified

What are the main mineral sources of phosphorus?

Correct Answer
verified

In the industrial electrolysis of aqueous NaCl (the chlor-alkali process), the modern trend is toward the use of cells incorporating polymer membranes to separate the anode and cathode solutions.

Correct Answer
verified

Exam 22: The Elements in Nature and Industry

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

Correct AnswerverifiedShow Answer

The Earth's core consists mainly of:

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

The ______________ process uses a boiling 30% sodium hydroxide solution to treat bauxite.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The most common source for commercial production of sodium is called

Correct AnswerverifiedShow Answer

What gas is produced at the anode in the Downs cell, in which molten NaCl is electrolyzed?

Correct AnswerverifiedShow Answer

Hydrometallurgy uses __________________ to separate a metal from its ore.

Correct AnswerverifiedShow Answer

The leaching of gold can be represented by the equation In this reaction, identify the oxidant, the reductant and the oxidation numbers of the elements which change.

Correct AnswerverifiedThe oxidant is O2, the reductan...View AnswerShow Answer

Correct AnswerverifiedBoth Al and Mg have strong, adherent, re...View AnswerShow Answer

Pyrometallurgy uses __________________ to separate a metal from its ore.

Correct AnswerverifiedShow Answer

Sulfur trioxide is the anhydride of sulfuric acid. However, SO3 is not added directly to water during the synthesis of sulfuric acid because

Correct AnswerverifiedShow Answer

Which one of the following species or compounds reacts at the cathode in the Hall-Héroult process?

Correct AnswerverifiedShow Answer

What gas is produced during the Hall-Héroult process for production of aluminum?

Correct AnswerverifiedShow Answer

What are the main mineral sources of phosphorus?

Correct AnswerverifiedShow Answer

In the industrial electrolysis of aqueous NaCl (the chlor-alkali process), the modern trend is toward the use of cells incorporating polymer membranes to separate the anode and cathode solutions.

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The oxidant is O₂, the reductan...
View Answer

Correct Answer
verified
Both Al and Mg have strong, adherent, re...
View Answer

Correct Answer
verified

Sulfur trioxide is the anhydride of sulfuric acid. However, SO₃ is not added directly to water during the synthesis of sulfuric acid because

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified