Carbon belongs to group IV and has four valence electrons. It exists in three allotropes: diamond, graphite, and buckminsterfullerene. Carbon forms more compounds than all other elements combined due to its ability to form chains and attach other atoms. Hydrocarbons are compounds of carbon and hydrogen, with natural sources including petroleum. Alkanes are saturated hydrocarbons with only carbon-carbon single bonds, while alkenes contain double bonds. Functional groups like alcohols and carboxylic acids distinguish other organic molecule families.

1. S. SHREYAS
X ‘B’
K.V.RWF

2.  Carbon belongs to the group IV of the periodic table.
 It has four electrons in its outermost orbit, so its valency
is four.
 Carbon is a non-metal.

3.  THERE ARE THREE FORMS OFPURE CARBON
 Diamond
 Graphite
 Buckminsterfullerene
“Bucky Balls”

4.  The number of carbon compounds is larger than that of
all other elements put together.

5.  Because carbon is chemically unique.
 Only carbon atoms have the ability to combine
with themselves to form long chains

6.  A long chain, in turn, provides a convenient backbone of
atoms to which other atoms can attach themselves in a
variety of ways

8.  On heating diamond or graphite in the air, they
burn completely to form carbon dioxide.
 Equal quantities of diamond and graphite when
burned, produce exactly the same amount of
carbon dioxide.

9.  Due to the difference in the arrangement of carbon
atoms in diamond and graphite

10.  Hydrocarbons are compounds of carbon and
hydrogen.
 The natural source of hydrocarbons is petroleum
(crude oil) .

12.  Methane CH4
A molecule of methane
has four hydrogen atoms
linked to one central
atom of carbon.

13. Alkanes are hydrocarbons that contain only
carbon-carbon single bonds.
◦ Every carbon atom participates in 4 single
bonds, either to another carbon or to a
hydrogen.
◦ Every hydrogen atom is bonded to a carbon by
a single bond.

15. ◦ Alkanes in which the carbons are connected in
a straight chain are called normal alkanes.
◦ Alkanes that are branched are called branched
chain alkanes.
C C C C C C
H
H
H
H H H H H
H
HHHHH
C C C C C H
H
H
H
C
H H H
HHHH
H
H
H

16.  Unsaturated hydrocarbons contain a double or
triple bond between two carbon atoms.
 The one with double bond are called alkenes.

18.  Unsaturated hydrocarbons which contain
triple bond between two carbon atoms.

19. ◦ They are often drawn to look like alkenes, but
they behave much differently than alkenes.
◦ They have an alternating pattern of double and
single bonds within a ring.
◦ Benzene is an example

20.  Compounds having the same molecular formulae
but different structural arrangement of atoms in
them are known as isomers, and the phenomenon
is known as isomerism
 Isomers of Butane – Obtained by rearranging the
carbon and the hydrogen atoms

21. In addition to the four families of hydrocarbons, there are
also many other families of organic molecules. These other
families include elements other than carbon and hydrogen.
◦ They exhibit a wide range of chemical and physical
properties.
◦ The families are distinguished by a group of atoms
called a functional group

22. ◦ Members of the alcohol family contain a hydroxyl
group.
◦ The hydroxyl group comprises an oxygen with one
single bond to a hydrogen and another single bond to
an alkane-type carbon
C C
H
H
H
H
H
O H
ethanol

23.  The carboxylic acid group can be attached to a
hydrogen, an alkane-type carbon, or an aromatic-type
carbon:
methanoic acid
(formic acid)
propanoic acid
C OH
O
H C OH
O
CC
H
H
H
H
H

24.  Chemically, esters can be synthesize by reacting
a carboxylic acid with and alcohol:
C
O
O CH2CH2CH3 CH3
Carboxylic
acid part
Alcohol
part
Ethylpropanoate

25. alcohols
carboxylic acids
esters