Carbon and its Compounds
Covalent bonds
The bonds formed by the sharing of electrons are known as covalent bonds.
In covalent bonding, both the atoms (that are participating in the bonding) share electrons,
i.e., the shared electrons belong to both the atoms.
Carbon contains four electrons in its valence shell. It always forms covalent bonds as it is
difficult for it to lose or gain four electrons in order to complete its octet.
Allotropes of Carbon
o Allotropes have different appearances and physical properties, but chemically they are the
same.
o There are three allotropes of carbon: diamond, graphite, and buckminsterfullerene.
Diamond Graphite Buckminsterfullerene
Amorphous Solid:
An amorphous solid is a non-crystalline solid with no well-defined ordered structure.
Amorphous forms of carbon are: Charcoal, Lampblack or soot; Coal; Coke
Catenation
Catenation is the ability of an element to combine with itself through covalent bonds.
Carbon shows extensive catenation, giving rise to large number of compounds.
It can form strong single, double, and triple bonds with other atoms of carbons. Carbon can
combine with itself to form chain, branched, and ring structures.
Hydrocarbons
The compounds made up of only carbon and hydrogen are called hydrocarbons.
The compounds of carbon that contain only single bonds among carbon atoms are called
saturated compounds
Compounds containing double and triple bonds among carbon atoms are called
unsaturated compounds.
, If the hydrocarbons are saturated (like methane and ethane), then they are called alkanes;
if they are unsaturated, then they are alkenes (containing double bonds) and alkynes
(containing triple bonds).
Aliphatic compounds
o Organic compounds that have a straight chain or branched chain structures.
o Example, methane, ethane, propane, 2-methylpropane etc.
o They are classified as:
Alkanes (contain only single bonds): General molecular formula is CnH(2n+2) where, n =
number of carbon atoms.
Alkenes (contain atleast one double bond): General molecular formula is CnH2n where, n =
number of carbon atoms.
Alkynes (contains atleast one triple bond): General molecular formula is CnH2n-2 where, n =
number of carbon atoms.
Alicyclic Saturated Hydrocarbons:
o Saturated organic compounds in which carbon atoms form a closed chain.
Aromatic Compounds
o Organic compounds that contain a ring system and have characteristic odour.
o First member is Benzene.
Structural Isomerism
o Organic compounds which have same chemical formula but differ in their structures are
known as isomers and this phenomenon is known as isomerism.
o For example, 2-methylpropane is the isomer of n-butane.
o Types of structure isomerism:
Chain/ skeletal/ nuclear isomerism: difference in the structure of the carbon chain that
forms the nucleus of the molecule
Position isomerism: difference in the position of the functional group, the carbon‒carbon
multiple bonds or the substituent group
Functional group isomerism: presence of different functional groups
Metamerism: difference in the number of carbon atoms on either side of the functional
group
Functional groups
o Carbon also forms covalent bonds with oxygen, nitrogen, and sulphur atoms.
o Presence of any of these elements in a compound confers specific properties to the
compound.
o A group of atoms that imparts specific properties to hydrocarbons is called a functional
group.
o Some functional groups in carbon compounds are shown in the given table.
Hetero atom Name of functional group Formula of functional group
Chlorine/Bromine Halo- (Chloro/Bromo) –Cl, –Br
Alcohol –OH
Aldehyde –CHO
Oxygen
Ketone >C=O
Carboxylic acid –COOH
Covalent bonds
The bonds formed by the sharing of electrons are known as covalent bonds.
In covalent bonding, both the atoms (that are participating in the bonding) share electrons,
i.e., the shared electrons belong to both the atoms.
Carbon contains four electrons in its valence shell. It always forms covalent bonds as it is
difficult for it to lose or gain four electrons in order to complete its octet.
Allotropes of Carbon
o Allotropes have different appearances and physical properties, but chemically they are the
same.
o There are three allotropes of carbon: diamond, graphite, and buckminsterfullerene.
Diamond Graphite Buckminsterfullerene
Amorphous Solid:
An amorphous solid is a non-crystalline solid with no well-defined ordered structure.
Amorphous forms of carbon are: Charcoal, Lampblack or soot; Coal; Coke
Catenation
Catenation is the ability of an element to combine with itself through covalent bonds.
Carbon shows extensive catenation, giving rise to large number of compounds.
It can form strong single, double, and triple bonds with other atoms of carbons. Carbon can
combine with itself to form chain, branched, and ring structures.
Hydrocarbons
The compounds made up of only carbon and hydrogen are called hydrocarbons.
The compounds of carbon that contain only single bonds among carbon atoms are called
saturated compounds
Compounds containing double and triple bonds among carbon atoms are called
unsaturated compounds.
, If the hydrocarbons are saturated (like methane and ethane), then they are called alkanes;
if they are unsaturated, then they are alkenes (containing double bonds) and alkynes
(containing triple bonds).
Aliphatic compounds
o Organic compounds that have a straight chain or branched chain structures.
o Example, methane, ethane, propane, 2-methylpropane etc.
o They are classified as:
Alkanes (contain only single bonds): General molecular formula is CnH(2n+2) where, n =
number of carbon atoms.
Alkenes (contain atleast one double bond): General molecular formula is CnH2n where, n =
number of carbon atoms.
Alkynes (contains atleast one triple bond): General molecular formula is CnH2n-2 where, n =
number of carbon atoms.
Alicyclic Saturated Hydrocarbons:
o Saturated organic compounds in which carbon atoms form a closed chain.
Aromatic Compounds
o Organic compounds that contain a ring system and have characteristic odour.
o First member is Benzene.
Structural Isomerism
o Organic compounds which have same chemical formula but differ in their structures are
known as isomers and this phenomenon is known as isomerism.
o For example, 2-methylpropane is the isomer of n-butane.
o Types of structure isomerism:
Chain/ skeletal/ nuclear isomerism: difference in the structure of the carbon chain that
forms the nucleus of the molecule
Position isomerism: difference in the position of the functional group, the carbon‒carbon
multiple bonds or the substituent group
Functional group isomerism: presence of different functional groups
Metamerism: difference in the number of carbon atoms on either side of the functional
group
Functional groups
o Carbon also forms covalent bonds with oxygen, nitrogen, and sulphur atoms.
o Presence of any of these elements in a compound confers specific properties to the
compound.
o A group of atoms that imparts specific properties to hydrocarbons is called a functional
group.
o Some functional groups in carbon compounds are shown in the given table.
Hetero atom Name of functional group Formula of functional group
Chlorine/Bromine Halo- (Chloro/Bromo) –Cl, –Br
Alcohol –OH
Aldehyde –CHO
Oxygen
Ketone >C=O
Carboxylic acid –COOH
