Question 1

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

Accepted Answer

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

Question 2

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

Accepted Answer

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

Question 3

-Which picture represents a p-type Si semiconductor?

Accepted Answer

A) picture (
A)  
B) picture (
B)  
C) both picture (
A) and picture (
B)  
D) neither picture (
A) nor picture (
B)  
A) picture (
A)  
B) picture (
B)  
C) both picture (
A) and picture (
B)  
D) neither picture (
A) nor picture (
B)

Question 4

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

Accepted Answer

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

Question 5

Look at the location of elements A,B,C,and D in the following periodic table.  
-Which of these elements is likely to be found in nature as a sulfide?

Accepted Answer

A) element A 
B) element B 
C) element C 
D) element D 
A) element A 
B) element B 
C) element C 
D) element D

Question 6

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

Accepted Answer

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

Question 7

Which one of the following is an electrical insulator?

Accepted Answer

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

Question 8

Picture (1)shows the electron populations of the bands of MO energy levels for elementary silicon.  
-Which picture (1)-(4)shows the electron populations when the silicon is doped with arsenic?

Accepted Answer

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

Question 9

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

Accepted Answer

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

Question 10

Which metal is not found in nature in uncombined form?

Accepted Answer

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

Question 11

The following pictures show the electron population of the bands of MO energy levels for four different materials.  
-Which of these materials has an electrical conductivity that increases with an increase in temperature?

Accepted Answer

A) materials (1)and (2) 
B) materials (1)and (4) 
C) materials (2)and (3) 
D) materials (3)and (4) 
A) materials (1)and (2) 
B) materials (1)and (4) 
C) materials (2)and (3) 
D) materials (3)and (4)

Question 12

Which substance is the best conductor of electricity?

Accepted Answer

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

Question 13

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

Accepted Answer

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 
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 14

The following pictures show the electron populations of the composite s - d bands for Y,Mo,Ag,and Cd.  
-Which picture corresponds to Cd?

Accepted Answer

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

Question 15

Steel is a mixture composed primarily of ________.

Accepted Answer

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

Question 16

One source of scandium is kolbeckite,which is a dihydrated phosphate of scandium.What is the formula of kolbeckite?

Accepted Answer

The answer of One source of scandium is kolbeckite,which is...

Question 17

The superconductor Tl2Ba2Ca2Cu3O10 has a critical temperature Tc = 125 K.In order for each of the atoms to have a whole-number oxidation number,the oxidation numbers of Tl,Ba,Ca,Cu,and O must be ________,________,________,________,and ________,respectively.

Accepted Answer

Question 18

The following picture shows the electron populations of the bands of MO energy levels for elementary silicon.  
-In this picture the conduction band is given by letter(s)

Accepted Answer

A) a) 
B) b) 
C) c) 
D) a and b. 
A) a) 
B) b) 
C) c) 
D) a and b.

Question 19

The following pictures show the electron populations of the composite s-d bands for Sc,Ti,V,and Zn.  
-Which picture corresponds to Ti?

Accepted Answer

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

Question 20

Which of the following is a semiconductor?

Accepted Answer

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

Exam 21: Metals and Solid-State Materials

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

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

-Which picture represents a p-type Si semiconductor?

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

Look at the location of elements A,B,C,and D in the following periodic table. -Which of these elements is likely to be found in nature as a sulfide?

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

Which one of the following is an electrical insulator?

Picture (1)shows the electron populations of the bands of MO energy levels for elementary silicon. -Which picture (1)-(4)shows the electron populations when the silicon is doped with arsenic?

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

Which metal is not found in nature in uncombined form?

The following pictures show the electron population of the bands of MO energy levels for four different materials. -Which of these materials has an electrical conductivity that increases with an increase in temperature?

Which substance is the best conductor of electricity?

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

The following pictures show the electron populations of the composite s - d bands for Y,Mo,Ag,and Cd. -Which picture corresponds to Cd?

Steel is a mixture composed primarily of ________.

One source of scandium is kolbeckite,which is a dihydrated phosphate of scandium.What is the formula of kolbeckite?

The superconductor Tl2Ba2Ca2Cu3O10 has a critical temperature Tc = 125 K.In order for each of the atoms to have a whole-number oxidation number,the oxidation numbers of Tl,Ba,Ca,Cu,and O must be ________,________,________,________,and ________,respectively.

The following picture shows the electron populations of the bands of MO energy levels for elementary silicon. -In this picture the conduction band is given by letter(s)

The following pictures show the electron populations of the composite s-d bands for Sc,Ti,V,and Zn. -Which picture corresponds to Ti?

Which of the following is a semiconductor?

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Nuclear Chemistry

Organic and Biological Chemistry

Filters

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

The superconductor Tl₂Ba₂Ca₂Cu₃O₁₀ has a critical temperature T_c = 125 K.In order for each of the atoms to have a whole-number oxidation number,the oxidation numbers of Tl,Ba,Ca,Cu,and O must be ,,,,and ,respectively.