Question 1

Which of the following refers to an alloy in which the composition is variable and the elements have comparable radii (within 15%)?

Accepted Answer

A) intermetallic 
B) interstitial 
C) Stoichiometric 
D) substitutional 
E) homogeneous 
A) intermetallic 
B) interstitial 
C) Stoichiometric 
D) substitutional 
E) homogeneous

Question 2

If a salt has a face-centered cubic fcc) unit cell and a 1:2 cation:anion stoichiometry with cations occupying the fcc positions, then the anions fill all the ______holes.

Accepted Answer

A) cubic 
B) octahedral 
C) tetrahedral 
D) octahedral and tetrahedral 
E) cubic, octahedral, and tetrahedral 
A) cubic 
B) octahedral 
C) tetrahedral 
D) octahedral and tetrahedral 
E) cubic, octahedral, and tetrahedral

Question 3

Gold has a face-centered cubic structure with a unit cell edge length of 407.8 pm.What is the density of each individual gold atom in g/cm3?

Accepted Answer

Question 4

Solder is a fusible metal alloy that is used to join together metal wires or work pieces.Old-style solder was often 60% tin( r = 140 pm) and 40% lead (r = 154 pm).Heating the solder caused it to melt; upon cooling, small sites would develop that were richer in Pb, which has a higher melting point than Sn. Cooled solder is thus best classified as

Accepted Answer

A) a homogeneous alloy. 
B) a heterogeneous alloy. 
C) an interstitial alloy. 
D) a colloidal alloy. 
E) an intermetallic compound. 
A) a homogeneous alloy. 
B) a heterogeneous alloy. 
C) an interstitial alloy. 
D) a colloidal alloy. 
E) an intermetallic compound.

Question 5

At a historic Civil War battleground, a stack of cannonballs looked like the picture below on the far left.Removing the top cannonball resulted in the middle view, and removing the next layer resulted in the view on the right.What sort of packing was used in stacking the cannonballs?

Accepted Answer

A) simple closest-packed 
B) hexagonal closest-packed 
C) cubic closest-packed 
D) random packed 
E) body-centered closest-packed 
A) simple closest-packed 
B) hexagonal closest-packed 
C) cubic closest-packed 
D) random packed 
E) body-centered closest-packed

Question 6

A salt with the formula AB has a ratio of ionic radii A/B = 0.28.Which structure is it likely to adopt?

Accepted Answer

A) rock salt 
B) sphalerite 
C) fluorite 
D) cubic 
E) There are insufficient data to determine the structure. 
A) rock salt 
B) sphalerite 
C) fluorite 
D) cubic 
E) There are insufficient data to determine the structure.

Question 7

Which of the following statements is NOT true about a crystallographic unit cell?

Accepted Answer

A) It repeats throughout a crystalline structure in three dimensions. 
B) It fills all the space in the crystalline lattice. 
C) Its dimensions can be measured with X-rays. 
D) It always has corners with 90$\degree$ angles. 
E) It represents the smallest repeating unit in the crystal. 
A) It repeats throughout a crystalline structure in three dimensions. 
B) It fills all the space in the crystalline lattice. 
C) Its dimensions can be measured with X-rays. 
D) It always has corners with 90$\degree$ angles. 
E) It represents the smallest repeating unit in the crystal.

Question 8

Iron extracted from ore tends to remain in an fcc structure after processing.If one-third of the octahedral holes are filled with carbon atoms, what is the chemical formula of the alloy?

Accepted Answer

Fe₃C There is the sam

Question 9

Classify the following solids as covalent network, molecular, amorphous, metallic, or ionic: 
A) rubber, 
B) glass, 
C) table sugar, 
D) table salt, 
E) silica, and, 
F) dry ice.

Accepted Answer

A) rubber-amorphous; 
B) glass

Question 10

Which two of the following elements are NOT found as a covalent network solid? 
I.beryllium, Be
II.carbon, C
III.phosphorus, P
IV.sulfur, S

Accepted Answer

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

Question 11

Which of the following is NOT an example of an ore?

Accepted Answer

A) hematite (Fe2O3) 
B) chalcocite( Cu2S) 
C) argentite (Ag2S) 
D) chalcopyrite (CuFeS2) 
E) quartz (SiO2) 
A) hematite (Fe2O3) 
B) chalcocite( Cu2S) 
C) argentite (Ag2S) 
D) chalcopyrite (CuFeS2) 
E) quartz (SiO2)

Question 12

Boron nitride, BN, is solid under standard conditions.Which of the following structures would you expect it to most resemble?

Accepted Answer

A) S8 
B) white phosphorus 
C) graphite 
D) carbon dioxide 
E) kaolinite 
A) S8 
B) white phosphorus 
C) graphite 
D) carbon dioxide 
E) kaolinite

Question 13

Which of the following can be varied to change the physical properties of an alloy? 
I.the elements used
II.the proportions used
III.the sites that each element occupies

Accepted Answer

A) I only 
B) II only 
C) III only 
D) I and II only 
E) I, II, and III 
A) I only 
B) II only 
C) III only 
D) I and II only 
E) I, II, and III

Question 14

The bonding in solid-state metals can be described as

Accepted Answer

A) nonexistent. 
B) a covalent network. 
C) highly directional. 
D) an electron sea. 
E) ionic. 
A) nonexistent. 
B) a covalent network. 
C) highly directional. 
D) an electron sea. 
E) ionic.

Question 15

The higher the carbon content in steel,

Accepted Answer

A) the stronger and more malleable it is. 
B) the stronger and more brittle it is. 
C) the weaker and more malleable it is. 
D) the weaker and more brittle it is. 
E) any of these, depending on the formula of the interstitial compound. 
A) the stronger and more malleable it is. 
B) the stronger and more brittle it is. 
C) the weaker and more malleable it is. 
D) the weaker and more brittle it is. 
E) any of these, depending on the formula of the interstitial compound.

Question 16

Silicon dioxide exists as a

Accepted Answer

A) covalent network solid. 
B) metallic solid. 
C) semimetallic solid. 
D) molecular solid. 
E) liquid. 
A) covalent network solid. 
B) metallic solid. 
C) semimetallic solid. 
D) molecular solid. 
E) liquid.

Question 17

Which of the following unit cells has the highest packing efficiency?

Accepted Answer

A) simple cubic 
B) face-centered cubic 
C) body-centered cubic 
D) both face-centered and body-centered cubic 
E) Simple, face-centered, and body-centered cubic all have the same packing efficiency. 
A) simple cubic 
B) face-centered cubic 
C) body-centered cubic 
D) both face-centered and body-centered cubic 
E) Simple, face-centered, and body-centered cubic all have the same packing efficiency.

Question 18

Pure solid metals

Accepted Answer

A) do not crystallize. 
B) are amorphous. 
C) often crystallize in closest-packed structures. 
D) often crystallize in very complex unit cells. 
E) crystallize in a wide variety of structures. 
A) do not crystallize. 
B) are amorphous. 
C) often crystallize in closest-packed structures. 
D) often crystallize in very complex unit cells. 
E) crystallize in a wide variety of structures.

Question 19

Mangalloy is a nonmagnetic steel with extreme antiwear properties.It contains approximately 0.8-1.25% carbon (r = 77 pm) and 11-15% manganese (r =127 pm), along with iron (r = 126 pm). Mangalloy is

Accepted Answer

A) a substitutional alloy. 
B) an interstitial alloy. 
C) both an interstitial and substitutional alloy. 
D) a colloidal alloy. 
E) an intermetallic compound. 
A) a substitutional alloy. 
B) an interstitial alloy. 
C) both an interstitial and substitutional alloy. 
D) a colloidal alloy. 
E) an intermetallic compound.

Question 20

Name two properties of a ceramic.

Accepted Answer

High melting point,

Exam 18: The Solid State a Particulate View

Which of the following refers to an alloy in which the composition is variable and the elements have comparable radii (within 15%)?

If a salt has a face-centered cubic fcc) unit cell and a 1:2 cation:anion stoichiometry with cations occupying the fcc positions, then the anions fill all the ______holes.

Gold has a face-centered cubic structure with a unit cell edge length of 407.8 pm.What is the density of each individual gold atom in g/cm3?

At a historic Civil War battleground, a stack of cannonballs looked like the picture below on the far left.Removing the top cannonball resulted in the middle view, and removing the next layer resulted in the view on the right.What sort of packing was used in stacking the cannonballs?

A salt with the formula AB has a ratio of ionic radii A/B = 0.28.Which structure is it likely to adopt?

Which of the following statements is NOT true about a crystallographic unit cell?

Iron extracted from ore tends to remain in an fcc structure after processing.If one-third of the octahedral holes are filled with carbon atoms, what is the chemical formula of the alloy?

Classify the following solids as covalent network, molecular, amorphous, metallic, or ionic: A) rubber, B) glass, C) table sugar, D) table salt, E) silica, and, F) dry ice.

Which two of the following elements are NOT found as a covalent network solid? I.beryllium, Be II.carbon, C III.phosphorus, P IV.sulfur, S

Which of the following is NOT an example of an ore?

Boron nitride, BN, is solid under standard conditions.Which of the following structures would you expect it to most resemble?

Which of the following can be varied to change the physical properties of an alloy? I.the elements used II.the proportions used III.the sites that each element occupies

The bonding in solid-state metals can be described as

The higher the carbon content in steel,

Silicon dioxide exists as a

Which of the following unit cells has the highest packing efficiency?

Pure solid metals

Mangalloy is a nonmagnetic steel with extreme antiwear properties.It contains approximately 0.8-1.25% carbon (r = 77 pm) and 11-15% manganese (r =127 pm), along with iron (r = 126 pm). Mangalloy is

Name two properties of a ceramic.

Matter and Energy an Atomic Perspective

Atoms, Ions, and Molecules the Building Blocks of Matter

Atomic Structure Explaining the Properties of Elements

Chemical Bonding Understanding Climate Change

Bonding Theories Explaining Molecular Geometry

Intermolecular Forces Attractions Between Particles

Stoichiometry Mass Relationships and Chemical Reactions

Aqueous Solutions Chemistry of the Hydrosphere

Thermochemistry Energy Changes in Chemical Reactions

Properties of Gases the Air We Breathe

Properties of Solutions Their Concentrations and Colligative Properties

Thermodynamics Why Chemical Reactions Happen

Chemical Kinetics Clearing the Air

Chemical Equilibrium Equal but Opposite Reaction Rates

Acid-Base Equilibria Proton Transfer in Biological Systems

Additional Aqueous Equilibria Chemistry and the Oceans

Electrochemistry the Quest for Clean Energy

Organic Chemistry Fuels, Pharmaceuticals, and Modern Materials

Biochemistry the Compounds of Life

Nuclear Chemistry the Risks and Benefits

The Main Group Elements Life and the Periodic Table

Transition Metals Biological and Medical Applications

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Gold has a face-centered cubic structure with a unit cell edge length of 407.8 pm.What is the density of each individual gold atom in g/cm³?