Chapter 2

Question 1

is a crystal that contains no point, line, or planar defects

Answer 1

perfect crystal

Question 2

are defects that occur only at or around a single lattice point

Answer 2

point defects

Question 3

are lines along which whole rows of atoms in a solid are arranged anomalously

Answer 3

line defects

Question 4

is discontinuity of the perfect crystal structure across a plane

Answer 4

planar defects

Question 5

occur where the crystallographic direction of the lattice abruptly changes.

Answer 5

grain boundaries

Question 6

occur in ordered alloys in this case the crystallographic direction remains the same, but each side of the boundary has an opposite phase

Answer 6

atiphase boundaries

Question 7

occur in a number of crystal structures, but the common example is close-packed structures

Answer 7

stacking fruits

Question 8

a defect that introduces a plane symmetry in the ordering of a crystal

Answer 8

twin boundary

Question 9

a state where there is no pattern or arrangements

Answer 9

no order

Question 10

arrangement of the atom extends only on the atom’s nearest neighbors

Answer 10

short-range order

Question 11

each water molecule in steam has short-range order due to the covalent bonds

Answer 11

steam water

Question 12

are joined together in a random manner. it may share corners, edgess, or faces

Answer 12

tetrahedral structure in silica

Question 13

orderliness repeated over infinitely great distances.

Answer 13

long range order

Question 14

have a crystalline structure in which the atoms or ions display long range order

Answer 14

MASCS
metals, alloys, semiconductors, ceramics, and some polymers

Question 15

material forms a regular repetitive, grid-like pattern, in three dimensions

Answer 15

crystalline materials

Question 16

the crystal lattice of the entire sample is continuous and unbroken to the edges of the sample, with no grain boundaries

Answer 16

single crystal

Question 17

small crystallites with different crystal orientations that are separated by grain boundaries

Answer 17

polycrystalline materials

Question 18

any material that exhibits only a short-range order of atoms or ions

Answer 18

amorphous materials

Question 19

are formed due to kinetics of the fabrication of the material

Answer 19

amorphous material

Question 20

a collection of lattice points, which are arranged in a periodic pattern

Answer 20

lattice

Question 21

why lattice points are arranged in periodic pattern?

Answer 21

so that each point is identical

Question 22

lattice can be how many dimensional

Answer 22

one, two, or three

Question 23

a group of one or more atoms located in a particular way

Answer 23

basis

Question 24

the smallest portion of a crystal lattice that shows the three dimensional pattern of the entire crystal

Answer 24

unit cell

Question 25

three dimensional arrangements of lattice points

Answer 25

bravais lattices

Question 26

a lattice named after auguste bravais who was an early french crystallographer

Answer 26

bravais lattices

Question 27

Seven crystal systems

Answer 27

MHROCTT monoclinic, hexagonal, rhombohedral, orthorhombic, cubic, triclinic, and tetragonal

Question 28

directions within the unit cell in which the atoms are in continuos contact are

Answer 28

close packed direction

Question 29

the number of atoms touching a given atom

Answer 29

coordination number

Question 30

space occupied by atoms

Answer 30

packing factor

Question 31

classifying solids based on bonds

Answer 31

MICM metallic solids, ionic solids, covalent network solids, and molecular solids

Question 32

are held together by a sea of collectively shared electrons

Answer 32

metallic solids

Question 33

sets of cations and anions mutually attracted to one another

Answer 33

ionic solids

Question 34

joined by an extensive network of covalent bonds

Answer 34

covalent network solids

Question 35

descrete molecules held together by weak forces

Answer 35

molecular solids

Question 36

long chains of atoms connected by covalent bonds, the chains are connected to other chains by weak forces

Answer 36

polymers

Question 37

crystlline compounds with the crystals on the order of 1-100 nm

Answer 37

nanomaterials

Question 38

solids with a regular repeating pattern of atoms is a

Answer 38

crystalline

Question 39

lack of order in the arrangement of atoms

Answer 39

amorphous solids

Question 40

basis of a repeating pattern is the unit cell

Answer 40

unit cell

Question 41

the structure of the crystalline solid is defined by

Answer 41

a. the size and shape of the unit cell b. the locations of atoms

Question 42

geometric pattern on which the unit cell is based

Answer 42

crystal lattice

Question 43

overall structure of the crystalline compound

Answer 43

lattice points

Question 44

connects the points and define the unit cell

Answer 44

lattice vectors

Question 45

have atoms only in the lattice points

Answer 45

primitive points

Question 46

have atoms in another regular location

Answer 46

centered lattices

Question 47

group of atoms that define the overall structure

Answer 47

motif

Question 48

structures of many metals conform to one of the cubic unit

Answer 48

metallic structure

Question 49

atoms in a crystal pack as close together as they can

Answer 49

close packing

Question 50

three common types of packing

Answer 50

CHC cubic close packed hexagonal close packed