Carbon exists in several allotropes with unique properties. Graphite has layered structures that allow for easy sliding of layers and is used as lubricant and pencil lead. Diamond has a tetrahedral structure and is the hardest material. Fullerenes like buckminsterfullerene have soccer ball shapes. Carbon also forms many inorganic compounds including carbon monoxide, carbon dioxide, carbonates, bicarbonates, carbides and cyanides that have various applications. Organic chemistry is the study of carbon compounds.

1. Chemistry of CarbonChemistry of Carbon
CompoundsCompounds
Properties of CarbonProperties of Carbon
AllotropesAllotropes
Inorganic Compounds of CarbonInorganic Compounds of Carbon
Organic ChemistryOrganic Chemistry

2. CARBONCARBON
 non-metallic element of group IV-A whichnon-metallic element of group IV-A which
constitutes only about 0.009 % by mass ofconstitutes only about 0.009 % by mass of
Earth’s crust. (but it is the 6Earth’s crust. (but it is the 6thth
most abundantmost abundant
element in the universe)element in the universe)
 exists in three isotopes:exists in three isotopes: 1212
C,C, 1313
C,C, 1414
CC
 has the unique ability to form long chainshas the unique ability to form long chains
(consisting of more than 50 C atoms) and(consisting of more than 50 C atoms) and
stable five or six-membered rings calledstable five or six-membered rings called
catenation.catenation.

3. Some Physical Properties ofSome Physical Properties of
CarbonCarbon
 Atomic number:Atomic number: 66
 Electron Configuration:Electron Configuration: 1s1s22
2s2s22
2p2p22
 Atomic mass:Atomic mass: 12.0107 amu12.0107 amu
 Melting Point:Melting Point: 3,823 K3,823 K
 Boiling Point:Boiling Point: 4,098 K4,098 K
 Density:Density: 2.2670 g/cm2.2670 g/cm33
 Phase (room temp.):Phase (room temp.): solidsolid

4. AllotropesAllotropes
 two or more forms of the same elementtwo or more forms of the same element
that differ significantly in chemical &that differ significantly in chemical &
physical properties.physical properties.

5. Allotropes of Carbon
 Crystalline-Crystalline- have highly ordered 3D structurehave highly ordered 3D structure
1.1. graphitegraphite
2.2. diamonddiamond
3.3. fullerenesfullerenes
 AmorphousAmorphous
1.1. carbon blackcarbon black
2.2. charcoalcharcoal
3.3. cokecoke

6. GraphiteGraphite
graphite is derived from the Greek wordgraphite is derived from the Greek word
“graphein” which means“graphein” which means to writeto write. It was. It was
named by the German Geologistnamed by the German Geologist
Abraham Werner in 1789.Abraham Werner in 1789.

7. Properties & Uses of
Graphite
 soft, greasy feel black mineralsoft, greasy feel black mineral
 is made up of layers of carbon, the Carbon atomsis made up of layers of carbon, the Carbon atoms
arranged in rings of 6 atoms.arranged in rings of 6 atoms.
 layers slide easily over each other because of thelayers slide easily over each other because of the
weak inter-layer forces (Van der Waal’s forces) butweak inter-layer forces (Van der Waal’s forces) but
inter atomic bonds are strong covalent bondsinter atomic bonds are strong covalent bonds
 contains free electrons, which move along layerscontains free electrons, which move along layers
 good conductor of heat & electricitygood conductor of heat & electricity
 used as pencil lead, lubricants, electrodes & rawused as pencil lead, lubricants, electrodes & raw
material for making synthetic diamondsmaterial for making synthetic diamonds

8. DiamondDiamond
 transparent crystalline solid, with high density
compared to other carbon allotropes
 hardest naturally occurring substance
 carbon atom is joined to 4 other Carbon atoms,
forming a Tetrahedron, or 4 sided figure held
together by covalent bonds
 used as cutting material, jewelries & for
decorative purposes

9. FullerenesFullerenes
 a class of carbon molecules in which thea class of carbon molecules in which the
carbon atoms are arranged into 12 pentagonalcarbon atoms are arranged into 12 pentagonal
faces and 2 or more hexagonal faces to form afaces and 2 or more hexagonal faces to form a
hollow sphere, cylinder, or similar figure.hollow sphere, cylinder, or similar figure.
 the most prominent of the fullerenes isthe most prominent of the fullerenes is
buckminsterfullerenebuckminsterfullerene , a spheroidal, a spheroidal
molecule, resembling a soccer ball, consistingmolecule, resembling a soccer ball, consisting
of 60 carbon atoms.of 60 carbon atoms.

10. FullerenesFullerenes
 fullerene research is expected to lead to newfullerene research is expected to lead to new
materials, lubricants, coatings, catalysts,materials, lubricants, coatings, catalysts,
electro-optical devices, and medicalelectro-optical devices, and medical
applications.applications.
 were first identified in 1985 by R. F. Curl, Jr.,were first identified in 1985 by R. F. Curl, Jr.,
R. E. Smally, and H. W. Kroto (who shared theR. E. Smally, and H. W. Kroto (who shared the
1996 Nobel Prize in Chemistry)1996 Nobel Prize in Chemistry)

11. STRUCTURE OF GRAPHITESTRUCTURE OF GRAPHITE

12. STRUCTURE OF DIAMONDSTRUCTURE OF DIAMOND

13. STRUCTURE OFSTRUCTURE OF
BUCKMINSTERFULLERENBUCKMINSTERFULLEREN
EE

14. Carbon BlackCarbon Black
 formed when hydrocarbons suchformed when hydrocarbons such
as methane are heated in a veryas methane are heated in a very
limited supply of oxygen:limited supply of oxygen:
CHCH44 + O+ O22 →→ CC(s)(s) + H+ H22OO
 used as pigment in black inksused as pigment in black inks
and making automobile tiresand making automobile tires

15. CharcoalCharcoal
 formed when wood is heated strongly informed when wood is heated strongly in
the absence of airthe absence of air
 used in filters to remove offensive odorsused in filters to remove offensive odors
from air and colored or bad-tastingfrom air and colored or bad-tasting
impurities form waterimpurities form water

16. CokeCoke
 impure form of carbon formed when coalimpure form of carbon formed when coal
((coalcoal- a fuel substance of plant origin, largely- a fuel substance of plant origin, largely
or almost entirely composed of carbon withor almost entirely composed of carbon with
varying amounts of mineral matter) is heatedvarying amounts of mineral matter) is heated
strongly in the absence of air.strongly in the absence of air.
 used as a reducing agent in metallurgicalused as a reducing agent in metallurgical
process.process.

17. Inorganic Compounds of
Carbon
 Oxides (carbon monoxide & carbon
dioxide)
 Carbonates
 Bicarbonates
 Carbides
 Cyanides

18. Carbon MonoxideCarbon Monoxide
 a colorless, odorless, toxic gas formeda colorless, odorless, toxic gas formed
by the incomplete combustion of carbon-by the incomplete combustion of carbon-
containing compounds.containing compounds.
 They are used for extracting nickels,They are used for extracting nickels,
organic synthesis and production oforganic synthesis and production of
hydrocarbon fuels with hydrogenhydrocarbon fuels with hydrogen

19. Carbon DioxideCarbon Dioxide
 a colorless, odorless, non-toxic gas.a colorless, odorless, non-toxic gas.
 it is an acidic oxide & used in beverages,it is an acidic oxide & used in beverages,
fire extinguishers, manufacture of bakingfire extinguishers, manufacture of baking
soda, NaHCOsoda, NaHCO33, and soda ash, Na, and soda ash, Na22COCO33..
 COCO22 can also exist in solid form, calledcan also exist in solid form, called
“dry ice”, which is used as a refrigerant.“dry ice”, which is used as a refrigerant.

20. CarbonatesCarbonates
 are compounds containing the anionare compounds containing the anion
COCO33
2-2-
 examples are calcium carbonate whichexamples are calcium carbonate which
can be found in egg shells, shells ofcan be found in egg shells, shells of
marine organisms & in both limestone &marine organisms & in both limestone &
marblemarble

21. CarbonatesCarbonates
 Calcium carbonateCalcium carbonate is normally water-is normally water-
insoluble. It will only dissolve in waterinsoluble. It will only dissolve in water
saturated with COsaturated with CO22 because carbonatedbecause carbonated
water (or carbonic acid) reacts withwater (or carbonic acid) reacts with
calcium carbonate to form calciumcalcium carbonate to form calcium
bicarbonate, which is water-soluble:bicarbonate, which is water-soluble:
CaCOCaCO3(s)3(s) + H+ H22COCO3(aq)3(aq)  CaCa2+2+
(aq)(aq) + 2HCO+ 2HCO33
--
(aq)(aq)

22. BicarbonatesBicarbonates
 are compounds containing the anion HCOare compounds containing the anion HCO33--
 example isexample is sodium bicarbonatesodium bicarbonate or bakingor baking
soda NaHCOsoda NaHCO33, a weak base added to recipes, a weak base added to recipes
to neutralize the acidity of other ingredients.to neutralize the acidity of other ingredients.
Baking soda is a mixture of baking soda andBaking soda is a mixture of baking soda and
a weak acid, like tartaric acid, that whena weak acid, like tartaric acid, that when
mixed with water, the acid reacts with themixed with water, the acid reacts with the
HCOHCO33
--
ion to form COion to form CO22 gas, which causes thegas, which causes the
dough or batter to rise.dough or batter to rise.
HCOHCO33
--
((aqaq)) HH++
((aqaq))  HH22COCO3(3(aqaq)) →→ HH22OO((ll)) + CO+ CO2(2(gg))

23. CarbidesCarbides
 ionic compounds formed from theionic compounds formed from the
combination of carbon & metalscombination of carbon & metals
 examples are CaCexamples are CaC22 (“carburo”) and(“carburo”) and
BeBe22C in which carbon is in the form ofC in which carbon is in the form of
CC22
2-2-
or Cor C4-4-
ions which are strong Bronstedions which are strong Bronsted
bases & reacts with water as:bases & reacts with water as:
CC22
2-2-
(aq)(aq) + 2H+ 2H22OO(l)(l) →→ 2OH2OH--
(aq)(aq) + C+ C22HH2(g)2(g)
CC4-4-
(aq)(aq) + 4H+ 4H22OO(l)(l) →→ 4OH4OH--
(aq)(aq) + CH+ CH4(g)4(g)

24. CarbidesCarbides
 another example is the covalentanother example is the covalent
compound of carbon with silicon calledcompound of carbon with silicon called
“carborundum” or silicon carbide, SiC.“carborundum” or silicon carbide, SiC.
 it is almost as hard as diamond & it hasit is almost as hard as diamond & it has
the diamond structure which can bethe diamond structure which can be
prepared from the reaction:prepared from the reaction:
SiOSiO2(s)2(s) + 3C+ 3C(s)(s) →→ SiCSiC(s)(s) + 2CO+ 2CO(g)(g)

25. CyanidesCyanides
 a carbon compound containing the aniona carbon compound containing the anion
group :CNgroup :CN≡≡N:N:--
 cyanide ions are extremely toxiccyanide ions are extremely toxic
 used in the metallurgy of gold in the formused in the metallurgy of gold in the form
of NaCNof NaCN