CHAPTER 2. NATURE OF MATERIALS
2.1. See Section 2.2.1.
2.3. See Section 2.1.1.
2.5. See Section 2.1.2.
2.7. See Section 2.1.2.
2.9. See Section 2.2.1.
2.10. If the atomic masses and radii are the same, then the material that crystalizes into a lattice
2.11. For the face-center cubic crystal structure
,
number of equivalent whole atoms in each unit
cell = 4
2.12. a.Number of equivalent whole atoms in each unit cell in the BCC lattice structure = 2
b. Volume of the sphere = (4/3) Sr3
18
c. Volume of the unit cell =
3
3
4»
¼
º
«
¬
ªr
celltheofvolumeunittotal
ce
ll
unitt
h
einatomso
f
vo
l
ume
A
PF
=
3
3
)3/4(
.)3/8(
r
r
S
=0.68
2.13. For the BCC lattice structure:
3
4r
a
3
4»
º
ªr
3
9
10124.04 »
º
ª
xx
Volume of the unit cell of copper =
)22( r
=
)1278.022( x
=
0.04723 nm
= 4.723 x10
m
2.16. For the BCC lattice structure:
3
4r
a
3
3
2329
10023.610348.2
xxx
2.17. For the BCC lattice structure:
3
4r
a
3
4»
º
ªr
3
9
101363.04 »
º
ª
xx
NV
AC
2329
10023.610119.3
xxx
19
2.18For the BCC lattice structure:
3
4r
a
3
4»
º
ªr
3
9
10128.04 »
º
ª
xx
NV
AC
2329
10023.610204.5
xxx
2.20. For the FCC lattice structure:
r
a22
3
3
3
-29
3
10023.61089.8
xxx
APF = 0.74 =
29
2.22. D
nA
U
For FCC lattice structure, n = 4
Vc=
23610023.61055.1
08.404
xxx
x
= 1.717 x 10-28 m3
20
b. APF = 0.74 =
28
3
10717.1
.)3/4(4
x
rx
S
r3= 0.7587 x 10-29 m3
r =0.196 x 10-9 m = 0.196 nm
2.23.
2.25. See Section 2.2.2.
2.27See Figure 2.14.
2.29. mt= 100 g
PB= 65 %
PlB = 30 %
2.30. mt= 100 g
PB= 45 %
PlB = 17 %
21
2.31. mt= 100 g
PB= 60 %
PlB = 25 %
2.32. mt= 100 g
PB= 40 %
PlB = 20 %
2.33.a. Spreading salt reduces the melting temperature of ice. For example, at a salt composition
of 5%, ice starts to melt at -21oC. When temperature increases more ice will melt. At a
2.34See Section 2.3.
2.36See Section 2.4.