Question 1

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 2

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

Accepted Answer

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

Question 3

What metal is isolated from the ore sphalerite?

Accepted Answer

A) chromium 
B) iron 
C) silver 
D) zinc 
A) chromium 
B) iron 
C) silver 
D) zinc

Question 4

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

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 5

The following pictures show the electron populations of the composite s-d bands for four different transition metals.  
-Which is the hardest metal?

Accepted Answer

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

Question 6

Why are ceramics so much more brittle than metals?

Accepted Answer

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. 
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 7

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 remains constant with an increase in temperature?

Accepted Answer

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

Question 8

Which element has the smallest energy band gap?

Accepted Answer

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

Question 9

Silica (SiO2)can be prepared from silicon ethoxide by the sol-gel process.Write a balanced equation for the hydrolysis of silicon ethoxide.

Accepted Answer

A) SiCl4 + 4 HOCH2CH3 + 4 NH3 → Si(OCH2CH3)4 + 4 NH4Cl (in benzene) 
B) Si(OCH2CH3)4 + 4 H2O → Si(OH)4 + 4 HOCH2CH3 
C) Si(OCH2CH3)4 + 4 HOCH3 → Si(OCH3)4 + 4 HOCH2CH3 
D) Si(OCH3)4 + 4 H2O → Si(OH)4 + 4 HOCH3 
A) SiCl4 + 4 HOCH2CH3 + 4 NH3 → Si(OCH2CH3)4 + 4 NH4Cl (in benzene) 
B) Si(OCH2CH3)4 + 4 H2O → Si(OH)4 + 4 HOCH2CH3 
C) Si(OCH2CH3)4 + 4 HOCH3 → Si(OCH3)4 + 4 HOCH2CH3 
D) Si(OCH3)4 + 4 H2O → Si(OH)4 + 4 HOCH3

Question 10

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 an oxide?

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 11

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

Accepted Answer

A) beryllia 
B) silicon carbide 
C) diamond 
D) aluminum 
A) beryllia 
B) silicon carbide 
C) diamond 
D) aluminum

Question 12

What minerals are important commercial sources of metals?

Accepted Answer

A) silicates 
B) chlorides 
C) nitrates 
D) oxides 
A) silicates 
B) chlorides 
C) nitrates 
D) oxides

Question 13

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 14

What is the average oxidation state of Cu in HgCa2Ba2Cu3O8-x if Hg is in the +2 oxidation state?

Accepted Answer

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

Question 15

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

Accepted Answer

A) +2 
B) +2.33 
C) +0.67 
D) +4.33 
A) +2 
B) +2.33 
C) +0.67 
D) +4.33

Question 16

What is a principal commercial ore for the element iron?

Accepted Answer

A) bauxite 
B) pyrolusite 
C) ilmenite 
D) hematite 
A) bauxite 
B) pyrolusite 
C) ilmenite 
D) hematite

Question 17

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

Accepted Answer

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

Question 18

The following pictures show the electron population of the bands of MO energy levels for four different materials.  
-Which of these materials has the lowest electrical conductivity?

Accepted Answer

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

Question 19

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

Accepted Answer

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 
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 20

Silicon nitride/zirconia is a example of a

Accepted Answer

A) ceramic-ceramic composite. 
B) ceramic-metal composite. 
C) ceramic-polymer composite. 
D) superconductor. 
A) ceramic-ceramic composite. 
B) ceramic-metal composite. 
C) ceramic-polymer composite. 
D) superconductor.

Exam 21: Metals and Solid-State Materials

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

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

What metal is isolated from the ore sphalerite?

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

The following pictures show the electron populations of the composite s-d bands for four different transition metals. -Which is the hardest metal?

Why are ceramics so much more brittle than metals?

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 remains constant with an increase in temperature?

Which element has the smallest energy band gap?

Silica (SiO2)can be prepared from silicon ethoxide by the sol-gel process.Write a balanced equation for the hydrolysis of silicon ethoxide.

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 an oxide?

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

What minerals are important commercial sources of metals?

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?

What is the average oxidation state of Cu in HgCa2Ba2Cu3O8-x if Hg is in the +2 oxidation state?

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

What is a principal commercial ore for the element iron?

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

The following pictures show the electron population of the bands of MO energy levels for four different materials. -Which of these materials has the lowest electrical conductivity?

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

Silicon nitride/zirconia is a example of a

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Silica (SiO₂)can be prepared from silicon ethoxide by the sol-gel process.Write a balanced equation for the hydrolysis of silicon ethoxide.

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

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