Chapter 11

Question 1

what does crystalline mean?

Answer 1

a solid in which atoms, molecules, or ions are arranged in patterns with long-range, repeating order

Question 2

what does amorphous mean?

Answer 2

a solid in which atoms or molecules do not have any long-range order

Question 3

what is Coulomb’s law?

Answer 3

E = q1q2/r

Question 4

what are intermolecular forces?

Answer 4

the forces between of attraction and repulsion between different molecules

Question 5

what is ion-induced dipole force?

Answer 5

an intermolecular force between ions and a non-polar molecule

Question 6

what are dispersion forces?

Answer 6

an intermolecular force (a type of ion-induced dipole force) exhibited by all atoms an molecules that result from fluctuations in the electron distribution

Question 7

what are dipole-dipole forces?

Answer 7

an intermolecular force exhibited by polar molecules that result from the uneven charge distribution

Question 8

what is a temporary dipole?

Answer 8

a permanent separation of charge; a molecule with permanent dipole always has a slightly negative charge at one end and a slightly positive charge at the other end

Question 9

what is miscibility?

Answer 9

the ability to mix without separating into two phases

Question 10

what is hydrogen bonding?

Answer 10

a strong type of intermolecular bonding that occurs between polar molecules that contain hydrogen atoms bonded directly to small electronegative atoms (FON)

Question 11

what is a hydrogen bond ?

Answer 11

a strong dipole-dipole attractive force between a hydrogen bonded to FON and one of these electronegative atoms on a neighbouring molecule

Question 12

what are dipole-induced dipole forces?

Answer 12

an intermolecular force between molecules that have a permanent dipole and an atom or molecule that is non-polar

Question 13

what are ion-dipole forces?

Answer 13

an intermolecular force between an ion and the oppositely charged end of a polar molecule

Question 14

what is surface tension?

Answer 14

The energy required to increase the surface area of a liquid by a unit amount: responsible for the tendency of liquids to minimize their surface, giving rise to a membrane-like surface

Question 15

what is viscosity?

Answer 15

a measure of the resistance of a liquid to flow

Question 16

what is capillary action?

Answer 16

the ability of a liquid to flow against gravity up a narrow tube due to adhesive and cohesive forces

Question 17

what does vaporization mean?

Answer 17

the phase transition from liquid to gas

Question 18

what is condensation?

Answer 18

the phase transition from gas to liquid

Question 19

what does volatile mean?

Answer 19

tending to vaporize easily

Question 20

what does nonvolatile mean?

Answer 20

not easily vapourized

Question 21

Summarize the process of water vaporization?

Answer 21

1. The rate of vaporization increases with increasing temperature
2. The rate of vaporization increases with increasing surface area.
3. The rate of vaporization increases with decreasing strength of intermolecular forces.

Question 22

what is melting point?

Answer 22

The temperature at which the molecules of a solid have enough thermal energy to overcome intermolecular forces and become a liquid

Question 23

what is melting (Fusion)?

Answer 23

the transition from solid to liquid

Question 24

what is freezing?

Answer 24

the transition from liquid to solid

Question 25

what is X-ray diffraction?

Answer 25

a powerful laboratory technique that allows for the determination of the powerful arrangement of atoms in a crystal and the measuring of the distance between them

Question 26

what is Bragg's Law ?

Answer 26

nλ =2d sinθ | distance between atomic layers = d = nλ/2d sinθ

Question 27

what is a crystalline lattice?

Answer 27

the regular arrangement of atoms in a crystalline solid

Question 28

what is a unit cell?

Answer 28

The smallest divisible unit of a crystal, that when repeated in 3D, reproduces the entire crystal lattice

Question 29

what is a simple cubic?

Answer 29

a unit cell that consists of a cube with one atom at each corner

Question 30

what is a coordinate number?

Answer 30

the number of molecules or ions directly bound to the metal atom in a complex ion

Question 31

what is packing efficiency?

Answer 31

The percentage of volume of a unit cell occupied by atoms, assumed to spherical

Question 32

what is the body-centred cubic?

Answer 32

a unit cell that consists of a cube with one atom at each corner and one atom at the centre of the cube coordinate number = 8

Question 33

what is the face-centred cubic?

Answer 33

a crystal structure whose unit cell consists of a cube with one atom at each corner and one atom in the centre of every face coordinate number = 12

Question 34

what is a hexagonal closet packing ?

Answer 34

a closet packed arrangement in which the atoms of the third layer align exactly over those in the first layer

Question 35

what is cubic closet packing?

Answer 35

a closet packed arrangement in which the third layer of atoms is offset from the first: the same structure as the faced-centred cubic

Question 36

what are molecular solids?

Answer 36

solids whose composite units are molecules; they generally have low melting points

Question 37

what are ionic solids?

Answer 37

solids whose composite units are ions; generally have high melting points

Question 38

what are atomic solids?

Answer 38

solids whose composite units are atoms, they include nonbonding atomic solids, metallic atomic solids, network covalent solids

Question 39

what are nonbonding atomic solids?

Answer 39

atomic solids held together by dispersion forces; they have low melting points

Question 40

what are metallic atomic solids?

Answer 40

atomic solids held together by metallic bonds; they have variable melting points

Question 41

what are network covalent atomic solids?

Answer 41

atomic solids held together by covalent bonds; they have high melting points

Question 42

what is band theory?

Answer 42

A model for bonding in atomic solids that comes from molecular orbital theory in which atomic orbitals combine and become delocalized over the entire crystal

Question 43

what is a band gap?

Answer 43

an energy gap that exists between the valence band and conduction band of semiconductors and insulators

Question 44

what is n-type semiconductor?

Answer 44

a semiconductor that employs negatively charged electrons in the condition band as the charge

Question 45

what is a diode?

Answer 45

a device that allows the flow of electrical current in only one direction

Question 46

what is a p-type semiconductor?

Answer 46

a semiconductor that employs positively charged "holes" in the valence band as the charge carriers

Question 47

what are p-n junctions?

Answer 47

tiny areas in electrical circuits that have a p-type semiconductors on one side and n-type on the other