???? ???? Chapter 14 The carbon family elements

1
???? ????Chapter 14 The carbon family elements
Carbon (C) Silicon (Si) Germanium (Ge) Stannum
(Sn) Plumbum (Pb)
Tin
Lead
2

• 14-1Carbon and its compounds
• ??General properties
• 1. ??s????,????sp2?sp3??,????
• ???4
• 2. ????????????,??CC?????
• ,?????????
• ????????????,?????????
• ????????

3

• ??Simple substance
• 1. ??????,???????????????
• F2?O2?N2???????,???? O2?N2
• ??????s??(??)???
• 2. Allotropes diamond graphite fullerene
  carbin (carbon fibers)
• (1) ? Scarbin gt Sgraphite gt Sdiamond
• (2) dc-c (nm) diamond gt graphite gt carbin

E (kJmol?1) 494 gt 210 210,
946 gt 250 250250
E (kJmol?1) 627 lt 374 374
4

• (3) Cgraphite Cdiamond ?H gt 0
  ?S lt 0
• ????,????6e91e10Pa,(because of
• the insignificant reduction of volume),????
• ????????,???????????????
• ,???????2000?,???????????
• ????????????(seed)????????
• ?( ??methane, ethane )?,?????1000?,?
• ??????????crystal whiskers
• CVD technique for diamond growth

5
Due to its combination of unique physical
properties diamond is an outstanding material.
Besides its unrivaled hardness diamond exhibits
ultrabroadband transparancy ranging from deep UV
to the microwave regime, and a thermal
conductivity at room temperature which is higher
than that of any other material. The excellent
mechanical, thermal, optical and insulating
properties of diamond became accessible through
the advent of low pressure Chemical Vapour
Deposition (CVD) techniques which allow diamond
in the form of extended films and free-standing
wafers to be fabricated.
The fundamental problem of diamond synthesis is
the allotropic nature of carbon. Under ordinary
conditions graphite, not diamond, is the
thermodynamically stable crystalline phase of
carbon. Hence, the main requirement of diamond
CVD is to deposit carbon and simultaneously
suppress the formation of graphitic sp2-bonds.
This can be realized by establishing high
concentrations of non-diamond carbon etchants
such as atomic hydrogen. Usually, those
conditions are achieved by admixing large amounts
of hydrogen to the process gas and by activating
the gas either thermally or by a plasma.  
6

• (4) C60
• ?12?????20??????,??????sp2
• ???????????????,???p???
• C60????????????p?,???????
• ??????(F) ???(V) ??(E) 2
• a. structure??????,??12??????
• ???????????????????
• C60???????????????
• ????????????C20

7
32??,60???,90?? 12??????20????? F V E 2
8
Fullerene Discoverers Win Chemistry Nobel The
Nobel Prize in chemistry was awarded today to two
Americans and one British researcher for their
discovery of fullerenes, a new class of
all-carbon molecules shaped like hollow
balls. The researchers, Richard E. Smalley and
Robert F. Curl Jr. of Rice University in Houston,
and Harold W. Kroto of the University of Sussex
in Brighton, United Kingdom, made their discovery
in 1985 in Smalley's lab at Rice while working
together to study how carbon atoms cluster. "The
award is richly deserved," says Robert Haddon, a
fullerene chemist at Lucent Technologies' Bell
Labs in Murray Hill, New Jersey. "It led to a
totally new field of chemistry." Today,
fullerenes--which are popularly known as
buckyballs--are being investigated for everything
from new superconductors and three-dimensional
polymers, to catalysts and optical materials,
although they have yet to spawn any commercial
applications. Before the group's discovery,
crystalline carbon was thought to adopt only a
handful of different molecular architectures,
including those found in diamond and graphite.
But the researchers discovered that sheets of
carbon atoms arranged in a pattern of hexagons
and pentagons can curl up and ultimately close to
form hollow cages. And because the number of
atoms in the cage can vary, an almost infinite
number of fullerene shapes may exist.
9
The Platonic Polydedra f2e-v
Tetrahedron Cube
Octahedron Dodecahedron
Icosahedron

• Triangles. The interior angle of an equilateral
  triangle is 60 degrees. Thus on a regular
  polyhedron, only 3, 4, or 5 triangles can meet a
  vertex. If there were more than 6 their angles
  would add up to at least 360 degrees which they
  can't. Consider the possibilities
• 3 triangles meet at each vertex. This gives rise
  to a Tetrahedron.
• 4 triangles meet at each vertex. This gives rise
  to an Octahedron.
• 5 triangles meet at each vertex. This gives rise
  to an Icosahedron
• Squares. Since the interior angle of a square is
  90 degrees, at most three squares can meet at a
  vertex. This is indeed possible and it gives rise
  to a hexahedron or cube.
• Pentagons. As in the case of cubes, the only
  possibility is that three pentagons meet at a
  vertex. This gives rise to a Dodecahedron.
• Hexagons or regular polygons with more than six
  sides cannot form the faces of a regular
  polyhedron since their interior angles are at
  least 120 degrees.

10

• b. properties ?????C60??21?????
• ??
• (i) C60??????????,????C60F2 ,?
• ??????
• (ii) C60??????????????????,
• ?????????????,?????
• (iii) C60???????,?????????,
• ????,?????????C60??????,?
• ??????,C60???????

11
Types of carbon nanotubes Single-walled

• The (n,m) nanotube naming scheme can be
  thought of as a vector (Ch) in an infinite
  graphene sheet that describes how to "roll up"
  the graphene sheet to make the nanotube. T
  denotes the tube axis, and a1 and a2 are the unit
  vectors of graphene in real space.

12
For a given (n,m) nanotube, if 2n m3q (where q
is an integer), then the nanotube is metallic,
otherwise the nanotube is a semiconductor. Thus
all armchair (nm) nanotubes are metallic, and
nanotubes (5,0), (6,4), (9,1), etc. are
semiconducting. In theory, metallic nanotubes can
have an electrical current density more than
1,000 times greater than metals such as silver
and copper.
13
(No Transcript)
14

• ??Compounds
• 1. - 4 O.S.
• ???(?????)
• Al4C3 12H2O 4Al(OH)3 3CH4?
• CaC2 2H2O Ca(OH)2 HCCH
• 2. 4 O.S
• (1) CHal4
• a. ?? CS2 3Cl2 CCl4 S2Cl2
• b. ?? ???

15

• CHal4 2H2O CO2 4HHal
• ??????????,???????????
• ??????????????,???????
• ?,????????
• ?CF4 CI4???????,??????,??
• ???,?????

16

• (2) COHal2(????????)
• ???COHal2?CHal4???????,????
• ????
• COCl2 H2O CO2 2HCl
• ??????,????????
• COCl2 (??) ????
• ?????
• CO Cl2 COCl2

17

• (3) CS2
• a. Preparation
• (i) C 2S CS2 (900?C)
• (ii) 4S CH4 CS2 2H2S (600?C,
  Al2O3???)
• b. Properties
• CS2???,??????????
• ???? CS2 2H2O CO2
  2H2S
• ???????? Na2S CS2 Na2CS3

18

• (4) CO32- CS32- CN22-
• a. structure
• b. ??
• (i) ??? ???????(???Li),??Tl?
• ??????,????????????????,?
• SNaHCO3 lt SNa2CO3
• ???????NaHCO3???HCO3-????
• ???????????,?????????
• ???? H2CO3 lt MHCO3 lt M2CO3

19

• (ii) ?????
• K2S CS2 K2CS3 H2CS3
• H2CS3????????,????H2S?CS2
• H2CS3???????,???????
• H2CS3 3H2O H2CO3 3H2S
• (iii) ????? (Cyanamide) (CN22-)(?????)
• H2CN2 ( Hydrogen dinitride carbonate )????
• ?,????,alcohol?ether,?????,??
• ??????????????

H
20

• H2CN2???????
• H2CN2 3H2O H2CO3 2NH3
• 3. 2 O.S.
• HCOOH CO H2O (???,??)
• CO??? ?µ??
• CO PdCl2 H2O Pd CO2 2HCl
• Cu(NH3)2????CO,??CO?N2??

??
CO2 v.s. CO
21

• 14-2 Silicon and its compounds
• ??General properties
• 1. ??Si??????,????,??????
• ????,??Si???????????????,??Si?Si????????pp-pp?
  ,???,Si?sp?sp2??????
• 2. ??Si????????3d???,??Si???
• ???????6,????dp??,??N(SiH3)3?N????sp2??,?????
  ????????N???????????Si???3d???,??d-pp??????N(CH3)3
  ?N(SiH3)3??????,???Lewis???????
• 3. Si?????????,????

22

• ??The simple substance
• 1. Properties
• (1) ??????,????? ,????????????
• ??,?????????
• 2Mg Si Mg2Si
• (2) ?????????????,????HFHNO3???
• ?? 3Si 4HNO3 18HF 3H2SiF6 4NO 8H2O
• (3) ???????H2 Si 2KOH H2O K2SiO3
  2H2?
• (4) ??????????? Si 3H2O H2SiO3 2H2?

23
Silicon nitride (Si3N4) is a hard, solid
substance, that can be obtained by direct
reaction between silicon and nitrogen at high
temperatures. Silicon nitride is the main
component in silicon nitride ceramics, which have
relatively good shock resistance compared to
other ceramics. Rollers made of silicon nitride
ceramic are sometimes used in high-end skateboard
bearings, due to the material's shock and
heat-resistant characteristics. It is also used
as an ignition source for domestic gas
appliances, hot surface ignition. In
microelectronics, silicon nitride is usually
formed using chemical vapor deposition (CVD)
method, or one of its variants, such as
plasma-enhanced chemical vapor deposition
(PECVD). It is usually used either as an
insulator layer to electrically isolate different
structures or as an etch mask in bulk
micromachining. As a passivation layer for
microchips, it is superior to silicon dioxide, as
it is a significantly better diffusion barrier
against water molecules and sodium ions, two
major sources of corrosion and instability in
microelectronics. It is also used as a dielectric
between polysilicon layers in capacitors in
analog chips. Bulk, monolithic silicon nitride is
used as a material for cutting tools, due to its
hardness, thermal stability, and resistance to
wear. It is especially recommended for high speed
machining of cast iron. For machining of steel,
it is usually coated by titanium nitride (usually
by CVD) for increased chemical resistance.
24
Lightning Arresters
In telegraphy and telephony a lightning arrester
is placed where wires enter a structure,
preventing damage to electronic instruments
within and ensuring the safety of individuals
near them. Lightning arresters, also called surge
protectors,are devices which are connected
between each electrical conductor in a power and
communications systems and the earth. These
provide a short circuit to the ground that is
interrupted by a non-conductor over which
lightning jumps. Its purpose is to limit the rise
in voltage when a communications or power line is
struck by lightning. The non-conducting material
may consist of a semi-conducting material like
silicon carbide or zinc oxide, or a spark gap.
Primitive varieties of such spark gaps are simply
open to the air, but more modern varieties are
filled with dry gas and provided with a small
amount of radioactive material to encourage the
gas to ionize when the voltage across the gap
reaches a specified level. Other designs of
lightning arresters use a glow-discharge tube
(essentially like a neon glow lamp) connected
between the protected conductor and ground, or
any one of a myriad of voltage-activated
solid-state switches called varistors or MOV's.
Lightning arresters built for substation use are
impressive devices, consisting of a porcelain
tube several feet in length and several inches in
diameter, filled with disks of zinc oxide. A
safety port is supplied on the side of the device
to vent the occasional internal explosion without
shattering the porcelain cylinder.
25

• 2. preparation
• (1) SiCl4 2Zn Si 2ZnCl2
• (2) SiO2?C??,??????
• SiO2 2C Si 2CO?
• (3) SiO2 CaC2 Si Ca 2CO
• (4) ????? SiH4 Si 2H2
• ??????????,???????????

gt99.999999
26
(No Transcript)
27

• ??Compounds
• 1. ???????????
• (1) IA? IIA???? Ca2Si , CaSi , CaSi2
• ???,????
• (2) ???????
• Mo3Si , Mo5Si3 , MoSi , MoSi2 (2050?)
• ????,???HF???,???HF
• HNO3?????????
• WSi2(2165?),Ti5Si3(2120?),V5Si3(2150?),f???????
  ??????????

28

• 2. 4 O.S. SiHal4,SiO2,Si3N4,SiC?SiH4
• (1) Structure
• ???????? SiO4 , SiS4 , SiN4 ,SiC4
• (2) properties
• a. ????
• SiO2 Ca(OH)2 CaSiO3 H2O
• SiH4 2KOH H2O K2SiO3 4H2
• CaS SiS2 CaSiS3

29

• b. Hydrolysis
• (i) SiCl4 4H2O H4SiO4 4HCl
• SiS2 4H2O H4SiO4 2H2S
• (ii) SiF4 3H2O H2SiO3 4HF
• 4HF 2SiF4 2H2SiF6
• ?3SiF4 3H2O H2SiO3 2H2SiF6
• (3) SiHal4??
• a. CaF2 H2SO4 CaSO4 2HF
• SiO2 4HF SiF4 2H2O
• b. SiO2 2C 2Cl2 SiCl4 2CO

30

• (4) ?? SinH(2n2) n???15
• a. preparation
• Mg2Si 2H2SO4 SiH4 2MgSO4
• Mg2Si 4NH4Br SiH4 2MgBr2 4NH3
• SiCl4(l) LiAlH4(s) SiH4(g) LiCl(s)
  AlCl3(s)
• b. properties
• (i) reduction
• SiH4 2KMnO4 2MnO2? K2SiO3 H2O H2?
• ???KMnO4?????????
• (ii) hydrolysis SiH4?????????????,??
• ????????,???????????

H2O
NH3
Silicone rubber
31

• (5) ??(Silicic acid)????
• a. ??????H , CO2 , NH4????H2SiO3
• b. ?????
• (i) ??SiO4???SiO14,????SiO44-
• (ii) ??SiO4?????,Si?O???????13.5,?
• ???Si2O72-
• (iii) SiO4??????????SiO4???????????????,Si
  O13
• (iv) SiO4????????,Si?O 4?11,
• (v) SiO4???????????SiO4???????
• (vi) SiO4??????????????????,SiO2

32
SiO13
33

• 14-3 Germanium Subgroup
• ??General properties
• 4???? Ge Sn Pb
  2????
• ????
  ????
• ??????tinstone ??(SnO2), galena (?
• ??) (PbS)
• ????Uranium ?Thorium??,??????U?Th????????

Pb??alpha, gamma?X-ray??beta?neutron???
34

• ??The simple substances
• 1. Allotropes
• ??(a?) ??(ß?) ??
• 2. Properties
• (1) Tin?????
• Sn 2HCl SnCl2 H2?
• Sn 2OH- 2H2O Sn(OH)42- H2? (??)
• (2) Ge???H2O2(???)???,????
• Ge 2KOH 2H2O2 K2 Ge(OH)6

13.6?C 161 ?C
35

• Pb??????
• Pb 2H2O 2KOH K2 Pb(OH) 4 H2?
  
• (2) ???????
• a. Pb?????????????Pb(NO3)2
• b. Sn??HNO3????Sn(IV),??HNO3???
• ?Sn(II)
• 3Sn 8HNO3 (?) 3Sn(NO3)2 2NO 4H2O
• Sn HNO3 (?) H2SnO3 NO2 H2O

36

• ??Compounds
• 1. ??? EHal4 EHal2
• (1) SnCl2
• a. ??? SnCl2 H2O Sn(OH)Cl? H
  Cl-
• ???SnCl2?????????
• ????????,??SnCl2???Sn??
• b. ???
• SnCl2 2HgCl2 SnCl4 Hg2Cl2
• Hg2Cl2 SnCl2 SnCl4 2Hg?

37

• (2) GeCl4 , SnCl4?????
• GeCl4 2H2O GeO2? 4HCl
• SnCl4 4H2O Sn(OH)4 4HCl
• ????SnCl4 2HCl H2SnCl6
• (3) PbCl2????????,????????
• ?,?????????
• ??PbCl2 2Cl- PbCl42-
• (4) PbCl4??????,???????
• PbCl4 PbCl2 Cl2

38

• 2. ???
• (1) SnS H2S Sn2 SnS?(???) 2H
• SnS???Na2S???,??????????
• HCl????????????
• SnS 4Cl- 2H SnCl42- H2S?
• (2) SnS2
• Sn4 2H2S SnS2? 4H
• SnS2 S2- SnS32-

2
39

• (3) PbS Pb2 S2- PbS?(??)
• PbS????HCl??HNO3?H2O2,???Na2S
• ????????
• PbS 4HCl(?) H2S? H2PbCl4
• 3PbS 2NO3- 8H
• 3Pb2 3S? 2NO? 4H2O
• ??Pb(IV)???????,??PbS2???

40

• 3. ???????
• (1) ???
• PbO(??) ???(massicot) Pb2O3(??) (PbOPbO2)
  Pb3O4(??) (2PbOPbO2) ?? PbO2(??)
• Pb2O3 , Pb3O4 , PbO2???????
• 5PbO2 2Mn2 4H 5Pb2 2MnO4- 2H2O
• PbO2 4HCl PbCl2 Cl2? 2H2O

41

• (2) Pb(NO3)2
• ???Pb2 NO3- H2O Pb(OH)NO3?H
• ???2Pb(NO3)2 2PbO 4NO2 2H2O
• (3) Pb(CH3COO)2
• ????,???,???
• Pb(Ac)2 Cl2 4KOH PbO2 2KCl 2KAc
  2H2O
• (4) PbSO4
• ????H2SO4?,????NH4Ac?NaAc???

42
H

• (5) PbCrO4(??) PbCr2O7(??)
• (6) ???????
• Na4Pb (????) 4C2H5Cl Pb(C2H5)4 4NaCl
• ??????????,??HfT217.6KJmol-1 ,
• ????????????
• ???Pb(C2H5)4???????,???????
• ?????????,????

OH-