Deck 8: Molecules and Materials

Question 1

Nonmetals have large band gaps and do not conduct electricity.

Answer 1

True

Question 2

Sodium chloride is an excellent example of a( n)_____.

A)amorphous solid
B)crystalline solid
C)covalent network
D)metallic solid

Answer 2

crystalline solid

Question 3

A substance that solidifies into a random molecular arrangement is referred to as an amorphous solid.

Answer 3

True

Question 4

A phase diagram provides detailed kinetics data on how fast a chemical reaction proceeds.

Question 5

Which of the following substances is an excellent conductor of electricity ?

A)Zinc
B)Silicon
C)Oxygen
D)Iodine

Question 6

How many "equivalent" atoms belong to a single face-centered cubic unit cell?

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

Question 7

_____ is the unoccupied band above the valence band .

A)Pauling's band
B)The conduction band
C)The induction band
D)The passive motion band

Question 8

Polymerization involves the linkage of several monomer units.

Question 9

If iridium has a density of 23.3 g\cm³and forms a face-centered cubic lattice, what is the atomic radius of the iridium atom?

A)135.7 pm
B)203.7 pm
C)271.4 pm
D)648.0 pm

Question 10

If the orbitals of two atoms overlap and interact with constructive interference, the resulting wave, which will have increased amplitude (or electron density)between the nuclei, is referred to as a( n)_____.

A)bonding molecular orbital
B)antibonding molecular orbital
C)free radical formation
D)cation formation

Question 11

To measure the vapor pressure of a liquid or a solid requires that the system reach equilibrium.

Question 12

Condensation polymers are made using a monomer with two functional groups that split off as the remainder of the two monomers are joined together. Often the small molecule eliminated in the process is water.

Question 13

The essential feature of the sea of electrons model is that the valence electrons of metal atoms do not move freely and are tied to specific atoms.

Question 14

If silver atoms follow a face-centered cubic unit cell pattern, what is the length of this unit cell if the atomic radius is 144.4 pm?

A)144 pm
B)179 pm
C)408 pm
D)635 pm

Question 15

In the context of dispersion forces, large molecules tend to be less polarizable than small ones.

Question 16

The ability to pull a metallic solid into a wire is called the metal's _____.

A)mobility
B)ductility
C)malleability
D)conductivity

Question 17

The manufacturing of semiconductors involves doping pure semiconductors, such as silicon or germanium, with controlled trace amounts of another element.

Question 18

How many "equivalent" atoms belong to a single body-centered cubic unit cell?

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

Question 19

Metals are _____, meaning they can be formed into useful shapes or foils .

A)brittle
B)ductile
C)malleable
D)conductors

Question 20

Additives such as plasticizers are often employed to improve the flexibility of polymers.

Question 21

In which of the following molecules  are you likely to observe hydrogen bonding?

A)NaF
B)C₂H₄F₂
C)Na₂O
D)HF

Question 22

Which pair of atoms is most likely to be involved in hydrogen bonding ?

A)H and F
B)Al and H
C)H and K
D)Na and H

Question 23

Which substance has the lowest vapor pressure ?

A)CClF ₃
B)propane (C₃H₈)
C)ethane (C₂H₆)
D)HCN

Question 24

Many current micro-electrical-mechanical systems (MEMS)devices begin with _____ as their primary component .

A)hydrogen
B)silicon
C)carbon
D)sodium

Question 25

Band gaps tend to be smallest for  _____.

A)conductors
B)semiconductors
C)insulators
D)modulators

Question 26

The sea of electrons model provides a quantitative understanding of metallic bonds .

Question 27

When a liquid reaches a temperature at which its vapor pressure is equal to one atmosphere, the liquid has reached its _____.

A)melting point
B)normal boiling point
C)sublimation point
D)evaporation point

Question 28

The packing efficiency of a body-centered cubic structure is more than a face-centered cubic structure .

Question 29

Which of the following substances has the highest boiling point?

A)C₈H₁₈
B)Kr
C)CH₂Cl₂
D)H₂O

Question 30

Doping pure silicon with gallium results in a(n)_____ material .

A)p-type
B)n-type
C)s-type
D)d-type

Question 31

In the molecular structure of propylene, if the methyl groups all point forward or backward, a(n)_____ is produced .

A)copolymer
B)atactic polymer
C)syndiotactic polymer
D)isostatic polymer

Question 32

In the context of band theory and conductivity, semiconductors have a larger band gap than insulators .

Question 33

The material etched during the creation of a micro-electrical-mechanical system device is referred to as the  _____.

A)substrate
B)counter layer
C)mask
D)retardant

Question 34

A p-type material can be made if pure germanium is doped with _____.

A)gallium
B)carbon
C)arsenic
D)silicon

Question 35

_____ involve side chains of one polymer attached to a backbone of a different polymer .

A)Alternating copolymers
B)Block copolymers
C)Graft copolymers
D)Random copolymers

Question 36

_____ is a polymer that can maintain its shape and strength when heated .

A)Polylactide
B)A thermosetting polymer
C)A thermoplastic polymer
D)Acrylonitrile butadiene styrene

Question 37

Which of the followings statements is true of dipole-dipole interactions ?

A)They are based on transient dipoles.
B)They are stronger than dispersion forces.
C)They are also referred to as instantaneous dipole-induced dipole forces.
D)They are also referred to as London forces.

Question 38

A p-type semiconductor can be formed if silicon is doped with an element that:

A) has more valence electrons than silicon.
B) has fewer valence electrons than silicon.
C) belongs to group 14 of the modern periodic table.
D) belongs to group 15 of the modern periodic table.

Question 39

Which of these materials provides an example of an ionic crystalline solid?

A)SrCl₂
B)C
C)SiC
D)C₆₀

Question 40

An addition polymerization must begin with the formation of a(n)_____.

A)free radical
B)electron pair
C)plasticizer
D)anion resin

Question 41

An n-type semiconductor can be formed if silicon is doped with an element that :

A)has more valence electrons than silicon.
B)has fewer valence electrons than silicon.
C)belongs to group 14 of the modern periodic table.
D)belongs to group 13 of the modern periodic table.

Question 42

Which of the following is the strongest of all intermolecular reactions ?

A)Dispersion forces
B)London forces
C)Dipole-Dipole interactions
D)Hydrogen bonding