carbon and its compounds. carbon carbon belongs to the group iv of the periodic table. carbon...
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CARBONCARBON Carbon belongs to the group Carbon belongs to the group
IV of the periodic table.IV of the periodic table. It has four electrons in its It has four electrons in its
outermost orbit, so its outermost orbit, so its valency is four.valency is four.
Carbon is a non-metal.Carbon is a non-metal.
Compounds of Carbon are Compounds of Carbon are Widely Distributed in NatureWidely Distributed in Nature
The number of carbon compounds is The number of carbon compounds is larger than that of all other elements larger than that of all other elements put together.put together.
Why so many Carbon Why so many Carbon Compounds in nature?Compounds in nature?
Because carbon is Because carbon is chemically unique.chemically unique.
Only carbon atoms Only carbon atoms have the ability to have the ability to combine with combine with themselves to themselves to form long chainsform long chains
Carbon- Long ChainsCarbon- Long Chains
A long chain, in turn, provides a A long chain, in turn, provides a convenient backbone of atoms to convenient backbone of atoms to which other atoms can attach which other atoms can attach themselves in a variety of waysthemselves in a variety of ways
Allotropes of CarbonAllotropes of Carbon
In nature, pure carbon occur in two In nature, pure carbon occur in two forms-forms-
DiamondDiamond GraphiteGraphite
What are Allotropes ?What are Allotropes ?
Allotropes are elements which are Allotropes are elements which are chemically identical, but they differ chemically identical, but they differ markedly in their physical properties.markedly in their physical properties.
Diamond and Graphite – two Diamond and Graphite – two allotropes of carbon differ in their allotropes of carbon differ in their physical properties.physical properties.
Physical Properties of Physical Properties of Diamond and GraphiteDiamond and Graphite
PropertyProperty DiamondDiamond GraphiteGraphiteAppearanceAppearance TransparentTransparent Black, ShinyBlack, Shiny
HardnessHardness Very HardVery Hard Soft, slippery to Soft, slippery to touchtouch
Thermal Thermal ConductivityConductivity
Very poorVery poor moderatemoderate
Electrical Electrical ConductivityConductivity
PoorPoor Good conductorGood conductor
Density(kg/m3)Density(kg/m3) 35103510 22502250
UsesUses Jewellery, Jewellery, drillingdrilling
Dry cell, Dry cell, electric arc, electric arc, lubricant, pencil lubricant, pencil leadlead
How Diamond and Graphite are How Diamond and Graphite are chemically identical?chemically identical?
These results of thes experiments answer this These results of thes experiments answer this question:question:
On heating diamond or graphite in the air, they On heating diamond or graphite in the air, they burn completely to form carbon dioxide.burn completely to form carbon dioxide.
Equal quantities of diamond and graphite when Equal quantities of diamond and graphite when burned, produce exactly the same amount of burned, produce exactly the same amount of carbon dioxide. carbon dioxide.
Why the physical properties of Why the physical properties of diamond and graphite are so diamond and graphite are so
different?different? Due to the difference in the Due to the difference in the
arrangement of carbon atoms in arrangement of carbon atoms in diamond and graphitediamond and graphite
HydrocarbonsHydrocarbons
Hydrocarbons are compounds of Hydrocarbons are compounds of carbon and hydrogen.carbon and hydrogen.
The natural source of
hydrocarbons is
petroleum (crude oil)
The Simplest HydrocarbonThe Simplest Hydrocarbon
Methane CHMethane CH44
A molecule of methane has four hydrogen atoms linked to one central atom of carbon.
AlkanesAlkanes
The hydrocarbons methane, ethane The hydrocarbons methane, ethane propane and butane form a series of propane and butane form a series of carbon compounds known as alkanescarbon compounds known as alkanes
The alkane series can be represented The alkane series can be represented by the general formula by the general formula
IsomerismIsomerism Compounds having the same molecular Compounds having the same molecular
formulae but different structural formulae but different structural arrangement of atoms in them are known arrangement of atoms in them are known as isomers, and the phenomenon is known as isomers, and the phenomenon is known as isomerismas isomerismIsomers of Butane – Obtained by rearranging the carbon and the hydrogen atoms
Unsaturated HydrocarbonsUnsaturated Hydrocarbons
Unsaturated hydrocarbons contain a Unsaturated hydrocarbons contain a double or triple bond between two double or triple bond between two carbon atoms. carbon atoms.
The one with double bond are called The one with double bond are called alkenesalkenes