P block element, Boron family , carbon family .

1. Boron FamilyBoron Family
Presented By : Nitin H. Bansod
Department of Chemistry
Shri Shivaji Science College,
Amravati.

2. THE GROUP 13 ELEMENTSTHE GROUP 13 ELEMENTS
Include boron, aluminum, gallium, indium and thallium.
Boron is the only nonmetal in the group many of their compounds of the
elements are electron deficient and act as Lewis acids. Aluminum is a metalloid
And gallium, indium and thallium are metals.
He
Li Be B C N O F Ne
Mg Al Si
Ca Ga Ge
Sr In Sn
Ba Tl Pb
Ra
1 2 13 14 15 16 17 0

3. Occurrence and recovery
Al – most abundant and Tl and In are least abundant.
B:- Borax; Na2B4O5(OH)4.8H2O and kernite; Na2B4O5(OH)4.2H2O;
Borax - Na2B4O5(OH)4.8H2O → boric acid, B(OH)3 → boron oxide, B2O3
→reduced with Mg, hydrofluoric acid, HF
Pure boron is produced by reduction of BBr3 vapour with H2:
2 BBr3(g) + 3 H2(g) → 2 B(g) + 6 HBr(g)
Al:- clays and aluminosilicate minerals and commercially as bauxite.
Gallium oxide occurs naturally as an impurity in bauxite and indium is obtained
in the Pb and Zn ores. Thallium compounds are found in the flue dust.

4. Element Symbol Atomic
No.
Electronic
Configuration
Valence shell
Configuration
Oxidation state
Boron B 5 [He] 2s2
2p1
2s2
2p1
III*
Aluminium Al 13 [Ne] 3s2
3p1
3s2
3p1
(1) III*
Gallium Ga 31 [Ar] 3d10
4s2
4p1
4s2
4p1
I III*
Indium In 49 [Kr] 4d10
5s2
5p1
5s2
5p1
I III*
Thallium Tl 81 [Xe] 4f14
5d10
6s2
6p1
6s2
6p1
I*
Inert
pair
effect
III

5. Properties of ElementsProperties of Elements
B Al Ga In Tl
Covalent radius/pm 80 125 125 150 155
Metallic radius/pm 143 141 166 171
Ionic radius(M+3
)/pm 27 53 62 94 98
Melting point/°C 2300 660 30 157 304
Boiling point/°C 3930 2470 2400 2000 1460
1st
I.E.I1/kj.mol-1
799 577 579 558 590
2nd
I.E.I2/kj.mol-1
2427 1817 1979 1821 1971
3rd
I.E.I3/kj.mol-1
3660 2745 2963 2704 2878
Electron affinity,
Ea/kj.mol-1
26.7 42.5 28.9 28.9
Pauling electronegativity 2.0 1.5 1.6 1.7 1.8
Eө
(M3+
;M)/V -0.89 -1.68 -0.53 -0.34 +1.26
Important.

6. Inert pair effectInert pair effect
Increased in nuclear charges of the Ga,In,Tl elements due to
the presence of their poor shielding 3d,4d and 4f orbital electrons. As effect of
this ns2
pair remain as inert , does not take part in chemical reaction. Only
np1
electron take part in the chemical reaction.
Tl 3+
+ 2e- Tl1+
unstable oxidizing agent stable reducing agent.
Electronic configuration – ns2
np1
, Boron family Generally exhibit
+3 oxidation state as lower down the group (+1) oxidation state is
more stable is called Inert pair effect.

7. Diagonal relationship of Be and AlDiagonal relationship of Be and Al
Physical propertiesPhysical properties
1.As Be and Al atom has small and high charge density, therefore it has1.As Be and Al atom has small and high charge density, therefore it has
strong tendency to form covalent compounds.strong tendency to form covalent compounds.
2. Std.oxidation potential (Be/Be2. Std.oxidation potential (Be/Be2+2+
= 1.70 & Al/Al= 1.70 & Al/Al3+3+
= 1.67 volts= 1.67 volts
3. Be and Al are rendered passive with conc.HNO33. Be and Al are rendered passive with conc.HNO3
4. Be and Al form many stable complexes.4. Be and Al form many stable complexes.
5.Electronegativity of both elements are same (Be=Al=1.5)5.Electronegativity of both elements are same (Be=Al=1.5)
6.Heat of Vaporization are same (293 KJ/mol)6.Heat of Vaporization are same (293 KJ/mol)
7. Be and Al do not impart any colour to flame.7. Be and Al do not impart any colour to flame.
Chemical propertiesChemical properties ::
1.Halides of Be and Al are soluble in Organic solvent and acts as lewis acid.1.Halides of Be and Al are soluble in Organic solvent and acts as lewis acid.
(BeCl(BeCl22 and AlCland AlCl33))

8. Chemical propertiesChemical properties
22.. Both BeO and AlBoth BeO and Al22OO33 are amphoteric in nature.are amphoteric in nature.
They dissolve in acid as well as in alkaliThey dissolve in acid as well as in alkali
BeO + 2HCl BeClBeO + 2HCl BeCl22 + H+ H22OO
BeO +2NaOH NaBeO +2NaOH Na22BeOBeO22 + H+ H22OO
AlAl22OO33 + HCl 2 AlCl+ HCl 2 AlCl33 + H+ H22OO
AlAl22OO33 + 2NaOH 2NaAlO+ 2NaOH 2NaAlO22
3. Be and Al both reacting with NaOH, liberating Hydrogen3. Be and Al both reacting with NaOH, liberating Hydrogen
Be +2NaOH NaBe +2NaOH Na22BeOBeO22 + H+ H22
22Al + 2NaOH + 2HAl + 2NaOH + 2H22O 2NaAlOO 2NaAlO22
4.Beryllium carbide(Be4.Beryllium carbide(Be22C) and aluminium carbide (AlC) and aluminium carbide (Al44CC33) form methane) form methane
BeBe22C + 2HC + 2H22O 2 BeO + CHO 2 BeO + CH44
AlAl44CC33 + 2H+ 2H22O 2 AlO 2 Al22OO33 + CH+ CH44

9. BORON COMPOUNDSBORON COMPOUNDS
HYDRIDES
Boron directly react with hydrogen, and form covalent compound called –
Borane hydride (Boranes).
These are electron deficient, colourless and diamagnetic compound and by
analogy with alkane called boranes
They are classfied into categories
Higher boranes are classified according to their electron count:
Type Formula skeletal electron pairs Examples
Closo BnHn
2-
n + 1 B5H5
2-
to B12H12
2-
Nido BnHn+4 n + 2 B2H6, B5H9, B6H10
Arachno BnHn + 6 n + 3 B4H10, B5H11
Hypho BnHn + 8 n + 4 none

10. B B
H
H
H
H H
H
Structure of diborane
Wade’s Rules: established by Kenneth Wade in the 1970s based on correlation
between the number of electrons, the formula and the shape of the molecules.
This apply to a class of polyhedral called deltahedra because they are made up
of triangular faces resembling Δ. For molecular and anionic boranes - predict
shapes of molecule or anion from its formula.
B-H bonds – 2c-2e
B-H-B bonds – 3c-2e
Diborane, like all boranes, is electron-deficient. There are 12 electrons (6 from
H and 3 each from B). The four B-H bonds use 8 electrons, leaving 2 electrons
each for the B-H-B bonds. The B-H-B bonds are therefore electron –deficient
(short of 4 electrons)

11. Characteristics reactions ofCharacteristics reactions of
boranes and borohydridesboranes and borohydrides
• Cleavage of BH2 unit from diborane or tetraborane by
NH3.
• Deprotonation of large boron hydrides by bases.
• Reaction of boron hydrides with borohydride ions to
produce larger borohydride anions.
• Fridel-Crafts type substitution for hydrogen in
pentaborane and some larger boron hydrides
B
-
H
H
H
H
B
-
B
-
H
B
-
H
H
H
H
H
B4H10
+ 2 :NH3 B
-H
H
N
+
N
+
H
HH
H
H
H +
B
-
H
H
B
-H
H
H
H
B
- H
H

12. Preparation of Diborane (B2H6)
1.From BCl3
2BCl3 + 5H2 B2H5Cl + HCl
B2H5Cl 5 B2H6 + 2BCl3
2. From BF3 with LiH
BF3 + 6 LiH B2H6 + 6 LiBF4
3. From NaBH4 :
NaBH4 + H2SO4 B2H6 + Na2SO4 + 2H2
4. From B2O3
B2O3 + 2Al + 3H2 B2H6 + Al2O3

13. Properties of Diborane
It is a colourless gas with sweet odour and extremely toxic.
B2H6
B(NH2)3
RNH2
B(OH)3 boric acid
6H2O
2KBO2 + 6H2
2KOH +2H2O
X3BPR3
PR3
B2 O3
O2
B4H10 + H2
Heat
REACTIONS OF B2H6 COMPOUNDS

14. Element Symbol Atomic
No.
Electronic
Configuration
Valence shell
Configuration
Oxidation state
Carbon C 6 [He] 2s2
2p2
2s2
2p2 +4
Silicon Si 14 [Ne] 3s2
3p2
3s2
3p2 +4
Germanium Ge 32 [Ar] 3d10
4s2
4p2
4s2
4p2
+2 +2
Tin Sn 50 [Kr] 4d10
5s2
5p2
5s2
5p2
+2 +2
Lead Pb 82 [Xe] 4f14
5d10
6s2
6p2
6s2
6p2
+2
Inert
pair
effect
+2

15. Positive oxidation state andPositive oxidation state and
Inert pair effectInert pair effect
Electronic configuration – ns2
np2
, Boron family Generally exhibit
+4 oxidation state as lower down the group (+2) oxidation state is
more stable is called Inert pair effect.
Increased in nuclear charges of the Ge,Sn,Pb elements due to
the presence of their poor shielding 3d,4d and 4f orbital electrons. As effect of this ns2
pair remain as inert , does not take part in chemical reaction. Only np2
electron take
part in the chemical reaction.
Ge 2+
+ 2e- Ge4+
Less stable More stable
Sn2+
Sn4+
reducing agent More stable
Pb4+
Pb2+
less stable oxidizing agent more stable

16. Negative oxidation stateNegative oxidation state
Due to low electro negativity : certain compounds like Be2C, Al4C3,
CaC2.. Contain C4-
and C2
2-

17. Structure of diamond and graphiteStructure of diamond and graphite

19. Carbide : it is a compound composed of carbon and a less electronegative element.
Carbides can be generally classified by chemical bonding type as follows:
(i) salt-like,
(ii) covalent compounds,
(iii) interstitial compounds

20. Salt-like carbides :
Salt-like carbides are composed of highly electropositive elements such as the alkali
metals, alkaline earth metals, and group 3 metals including Sc, Y and La. Al from
group 13 forms carbides,
These materials feature isolated carbon centers, often described as "C4−
", in the
methanides or methides:
Be2C + 4H2O 2Be(OH)2 + CH4
Al4C3 + 12H2O 4 Al(OH)3 + 3CH4
two-atom units, "C2
2−
", in the acetylides
Na2C2 + 2H2O 2NaOH + C2H2
CaC2 + H2O Ca(OH)2 + C2H2

21. Covalent carbides:
The carbides of silicon and boron are described as "covalent carbides",
although virtually all compounds of carbon exhibit some covalent
character. Silicon carbide (SiC)has two similar crystalline forms, which
are both related to the diamond structure.
Boron carbide, B4C, on the other hand, has an unusual structure which
includes icosahedral boron units linked by carbon atoms. In this respect
boron carbide is similar to the boron rich borides.
Both silicon carbide (also known as carborundum) and boron carbide
are very hard materials and refractory. Both materials are important
industrially. Boron also forms other covalent carbides, e.g. B25C

22. Interstitial carbides:
The carbides of the group 4, 5 and 6 transition metals (with the exception of chromium)
are often described as interstitial compounds.These carbides have metallic properties
and are refractory. Some exhibit a range of stoichiometries, e.g. titanium carbide, TiC.
Titanium carbide and tungsten carbide are important industrially and are used to coat
metals in cutting tools.
The longheld view is that the carbon atoms fit into octahedral interstices in a close
packed metal lattice when the metal atom radius is greater than approximately 135 pm
When the metal atoms are cubic close packed, (ccp), then filling all of the octahedral
interstices with carbon achieves 1:1 stoichiometry with the rock salt structure.

23. FullerenesFullerenes
• Fullerenes are a family of carbon allotropes.
• The general formula of this series is C2n where
n= 14 to 48
if n < 40 it may have odd or even no.
if n> 40 it has always even no. C60,C70,C76,C78

24. PreparationPreparation
• Passing current from Graphite rod in inert atm.(Argon) at 200
torr pressure ----- Fluffy mass ---Fullerene soot.
Soluble in benzene, isolated and purified by chromatographic method and then purified
by sublimation in vacuum.
Properties : Magenta colour, Most symmetric in 3D, Round less,
edgeless,Chargeless,bouncy ball, spin over 1 billion per second

25. Discovery of the first fullerene: C60Discovery of the first fullerene: C60
• In 1985, Prof. Harold W. Kroto of the University
of Sussex joined Robert F. Curl and Prof.
Richard E. Smalley at Rice University to study
the products of carbon vaporization.
• They carried out molecular beam experiments.
• From the result, discrete peaks were observed
corresponding to molecules with the exact mass
of sixty or seventy or more carbon atoms.
• C60 was then discovered, and it was named
buckminsterfullerene which is named after
Richard Buckminster Fuller who designed
geodesic domes which is the same structure as
C60.
• Shortly after discovery of C60, it came to
discover the fullerenes.
Harold Kroto
Richard Errett Smalley
Robert Floyd Curl

26. Construction of the model of C60Construction of the model of C60
• Cut out 12 pieces of regular pentagon
paper and 20 pieces of regular hexagons
paper, keeping the length of their sides
as the same.
• Use transparent tape to attach the
shapes together.
• Each pentagon should be surrounded by
5 hexagons. Hexagons should be
surrounded by three hexagons and three
pentagons placed next to each other
alternately.
• Fold up the large piece of paper to form a
ball just as shown in the picture at the
left. A model is finished!

27. Structures of some fullerenesStructures of some fullerenes
• C60 (Buckminsterfullerene)
• 20 hexagon and 12 pentagon
C-C and C=C bond
it is like the shape ofit is like the shape of
a footballa football
*grey ball represents a carbon atom

28. Structures of some fullerenesStructures of some fullerenes
- structure consists
of 12 pentagons as
faces only
*grey ball represents a carbon atom
 C20 (the smallest possible fullerene)C20 (the smallest possible fullerene)

29. Applications of fullerenesApplications of fullerenes
• 1)They have synthetic , Pharmaceutical and Industrial application.
• 2) They are used as support for Pd and Pt catalyst.
• 3) They are used in preparation of diamond films
• 4) Their derivative exhibit fascinating electrical and magnetic
behavior, Superconductivity.
• 5)Carbon Nanotubes - nanotubes are cylindrical fullerenes. These
tubes of carbon are usually only a few nanometers wide, but they have
high tensile strength, high electrical conductivity, high resistance to
heat, and relative chemical inactivity.
These tubes can help to make useful substances. For examples:
- tennis racket
- superconductor
- composite used in aircraft

34. Element Symbol Atomic
No.
Electronic
Configuration
Valence shell
Configuration
Oxidation state
Nitrogen N 7 [He] 2s2
2p3
2s2
2p3
+5
Phosphorus P 15 [Ne] 3s2
3p3
3s2
3p3
+5
Arsenic As 33 [Ar] 3d10
4s2
4p3
4s2
4p3
+3 +3
Antimony Sb 51 [Kr] 4d10
5s2
5p3
5s2
5p3
+3 +3
Bismuth Bi 83 [Xe] 4f14
5d10
6s2
6p3
6s2
6p3
+3
Inert
pair
effect
+3
Nitrogen family (VA) Group

35. Negative oxidation state &PositiveNegative oxidation state &Positive
oxidation Stateoxidation State
Negative oxidation state :
Li3N,Ba3N2,Ca3N2 (nitride, N3-
)
Na3P,Ca3P2,(Phosphide P3-
)AsH3,SbH3,BiH3
Nitrogen show variety of oxidation state:
+1 : N2O, +2: NO, +3 : N2O3, +4 : N2O4, +5 : N2O5
Positive oxidation state :
These element show +3 & +5 Oxidation state when they combine with more
electronegative element
+3 Oxidation state
Phosphorus : PCl3,PF3,P2O3
Arsenic : AsCl3,AsI3,
Antimony : SbF3,SbI3,Sb2O3

36. +5 oxidation state+5 oxidation state
Nitrogen : HNO3,N2O5
Phosphorus : PCl5, POCl3, P2O5,
Arsenic : As2O5,
Antimony : Sb2O5,SbCl5.
Bismuth : Bi2O5,NaBiO3

37. Anomalous Behavior of NitrogenAnomalous Behavior of Nitrogen
This is due to, Small size, High electro negativity and availability of d-Orbital in a
valence shell.