carbon

1. TOPIC 3
CARBON COMPOUND
CERTIFICATES OF HEALTH SCIENCE
CS1064 CHEMISTRY II
MDM SITI BAINUN BINTI MOHD DALI

2. LEARNING OUTCOMES
• State the definition of carbon compound
• Identify different types of carbon compounds
• Explains homologous series
• Construct molecular formula and structural formula, and name the
members of the homologous series
• Describe physical properties of the compounds in a homologous
series

3. INTRODUCTION
Carbon compounds:
compounds that contain carbon as one of their
constituent elements.

4. WHY CARBON IS UNIQUE
•Forms four covalent bonds
•Bonds covalent to: H, O, N, P,
S and all other nonmetals
(except noble gas)
•Carbon atoms join to form:
•Chain
•Rings

5. WHY CARBON IS UNIQUE
• Carbon can form multiple bonds to itself; oxygen and
nitrogen to give large variety of compounds
• The number of compound is so large that a separate
branch of chemistry – organic chemistry is devoted to
the study of these compound
• Carbon atoms able to form long chains of carbon atom.
This property is known as catenation

6. Carbon Bond

7. Carbon
Compounds
Organic Compound Inorganic Compounds
• Carbon-containing
compounds that can
be obtained from living
things
• Except oxides of
carbon, carbonates,
cyanides, and metallic
carbides
• Non-carbon-containing
compounds that can
be obtained from non-
living things
• Include oxides of
carbon, carbonates,
cyanides, and metallic
carbides

8. ORGANIC COMPOUNDS

10. HYDROCARBON
• The simplest organic compounds:
• Containing only carbon and hydrogen
• It can be separated intro three main groups:
• Saturated
• Unsaturated
• Aromatic

11. Saturated Hydrocarbon
• Hydrocarbon that contain only single
bonds between carbon atoms
• The simplest class of hydrocarbon
• Called saturated because each
carbon atom is bonded to as many
hydrogen atoms as possible
• In other words, carbon atoms are
saturated with hydrogen
• Types of saturated hydrocarbon:
alkanes

12. Unsaturated & Aromatic
Hydrocarbon
Unsaturated hydrocarbon
• Contain double or triple bonds between
carbon atoms
• Types of unsaturated hydrocarbons: alkene,
alkyne and aromatic ring
Aromatic hydrocarbon
• Contain benzene rings or similar features
The saturated and unsaturated hydrocarbons
are often referred as the aliphatic
hydrocarbons.

13. HOMOLOGOUS SERIES

14. Homologous Series
Homologous series has the following characteristics:
• Same general formula
• Same chemical formula
• Same chemical properties
• Consecutive members differ by one carbon atom and two
hydrogen atoms
• Physical properties that gradually change from one member
to the next

15. HOMOLOGOUS SERIES

16. NAMING OF CARBON COMPOUND (IUPAC)
• Naming of carbon compound: have 2 components

17. • Stem/root

18. • Suffix/ending

19. ALKANES

20. ALKANES
• Methane (CH4) is the simplest alkanes which 4 hydrogen
atoms are linked to the carbon atoms in a tetrahedral
• Instead of hydrogen atom, the carbon atom is further
linked to another carbon atom, we got another alkane
namely ethane (C2H6)
• General formula of alkanes: CnH2n+2, n=1,2,3

21. RULES FOR NAMING ALKANES
1. Find the longest carbon chain in the compound. This gives the
parent name of the compound.
5C
5C
3C
Longest carbon chain is 5: parent name is Pentane

22. 2. Number each carbon atom in the longest chain, starting
from the end nearest to the branch. This means that the
number appearing in the name is smaller number.
1
2
3
4
5
BRANCH

23. 3. Name the group joined to the chain and state the number
of the carbon atom to which it is joined.
2
Methyl group
2-methylpentane

24. 4. If the chain has 2 more identical groups joined to it.
Prefixes like di, tri, tetra are used to indicate the number of
groups present.
2
Methyl groups
2,4-dimethylheptane
1 3 4 5 6 7
No of groups
present
Prefixes
2 Di-
3 Tri-
4 Tetra-

25. 5. If a chain has 2 or more different groups joined to it, the
groups are written in alphabetical order i.e. ethyl before
methyl
2
Methyl group
4-ethyl-2-methylhexane
1
3
4
5
6
Ethyl group

26. Two common branches:
Methyl group
- CH3
Ethyl group
-CH3CH2

27. Example: name this alkane
2,2-dimethylpropane

28. PHYSICAL PROPERTIES OF ALKANES
• Colourless and odourless compound
• Dissolve in organic solvent
• Less dense than water
• Cannot conduct electricity
• Insoluble in water
• Low melting and boiling point: because the molecules
are held together by weak intermolecular forces
which can be overcome by small amount of energy

29. PHYSICAL PORPERTIES OF ALKANES

30. CHEMICAL REACTIONS OF ALKANES
• All alkanes have similar chemical properties because
they belong to the same homologous series
• Alkanes are unreactive; they do not react with most
chemicals
• They undergo two main types of reaction:
• Combustion (complete & incomplete)
• Substitution reaction

31. 1.a) Combustion Reaction (Complete)
• Alkanes burn in a
plentiful supply of air to
release energy (the
reasons why they are
used as fuel)
Gas
supplied
here refers
to alkanes

32. 1.a) Combustion (Complete)
• Burning (properly called combustion) also produces:
• CO2
• Water vapour (H2O)
• Heat
Lets observe what happened when you light a
Bunsen burner!

33. 1.a) Combustion (Complete)
1. Methane gas (CH4) exits
from the mouth of the
Bunsen Burner and mixes
with the oxygen gas (O2) in
the atmosphere
2. A flame is placed near the
mouth of the Bunsen Burner.

34. 1.a) Combustion (Complete)
3. Methane gas burns in oxygen
gas
4. The product of the combustion
are CO2 and H2O
5. Complete combustion  blue,
non-luminous flame

35. 1.a) Combustion (Complete)
Writing a balance equation : complete combustion of methane
Word equation: methane + oxygen  carbon dioxide + water + heat
Note: heat is always evolved from the combustion
Chemical Equation:
Step 1: write chemical equation
CH4 + O2  CO2 + H2O
Step 2: balance the equation
CH4 + O2  CO2 + 2 H2O

36. 1.b) Combustion (Incomplete)
Some important pointers on complete combustion
• When there is insufficient oxygen gas, incomplete
combustion occurs.
• Note: incomplete combustion also occurs for larger
alkanes (e.g candle wax C22H52)
• Its means that the alkanes is not burnt completely and
gives more sooty flame (orange-yellow in colour)
• The black soot is carbon and the yellow flame comes from
glowing carbon atoms.

37. 1.b) Combustion (Incomplete)
What happen if there is insufficient Oxygen?
The possible balanced chemical equation for the
incomplete combustion of methane gas is:
CH4 + O2  C + 2H2O [carbon only]
2CH4 + 3O2  2CO + 4H2O [carbon monoxide only]
4CH4 + 5O2  2CO2 + 2C + 8H2O [mixture of both]

38. 2. Substitution Reaction
• Alkanes react with halogens, such as chlorine and bromine, in the
presence of ultraviolet light (UV Light)
• For example:
Methane react with chlorine to form chloromethane and hydrogen
chloride gas.
CH4 + Cl2  CH3Cl + HCl
This is substitution reactions. The hydrogen atom in methane is
replaced by chlorine atom

39. 2. Substitution Reaction
• More hydrogen atoms can be replaced with chlorine atoms to
produce a mixture of four organic compound

40. 2. Substitution Reaction
Writing out entire sequence of reaction
• More hydrogen atoms can be replaced with chlorine atoms to
produce a mixture of four organic compounds!
CH4 + Cl2  CH3Cl + HCl
CH3Cl + Cl2  CH2Cl2 + HCl
CH2Cl2 + Cl2  CHCl3 + HCl
CHCl3 + Cl2  CCl4 + HCl
dichloromethane
trichloromethane
tetrachloromethane

41. Halogenation
• Reactions of alkanes with halogens
• Take place readily in sunlight/ultraviolet
• Example of substitution reaction
Reaction that occurs when one
atom or a group of atoms in a
molecule is replaced by another
atom or group of atoms

42. ALKENES

43. ALKENES
• Contain at least one carbon-carbon double bond (C=C)
• General formula, CnH2n (n= 2,3,4,…..)
• Classified as unsaturated hydrocarbons (compound with double or
triple carbon-carbon bonds that enable them to add hydrogen atoms
• For example:
C2H4 – ethylene
CH2=CH2

44. Naming Alkenes
1. Select the longest
continuous carbon
chain that contains a
double bond
2. Name the parent
compound octene.
Select it as the parent
compound

45. Naming Alkenes
3. Number the carbon chain
of the parent compound
starting with the end
nearer to the double
bond. Use the smaller of
the two numbers on the
double-bonded carbon to
indicate the position of
the double bond. Place
this number in front of
the alkene name.
This end is the
closest to the
double bond.
1
2
3
4
5
6
7
8
1 - octene

46. Naming Alkenes
4. Branched chains and other
groups are treated as in
naming alkanes. Name the
substituent group, and
designate its position on the
parent chain with a number
1
2
3
4
5
6
7
8
4-ethyl-1 - octene
The ethyl group
is attached to
carbon 4

47. Naming Alkenes
• A compound with more than one double bond
―Two double bond: diene
―Three double bond: triene
―Four double bond: tetraene
* Numbers are used to specify the locations of the double bonds
IUPAC names: buta-1,3-diene
IUPAC names: hepta-1,3,5-triene
1
2
3
4
1
2
3
4
5
6
7
IUPAC names: cycloocta-1,3,5,7-tetraene

48. Cycloalkenes
• Contains C=C in the ring
• Nomenclature of cycloalkenes:
―Similar to that alkenes
―Carbons atoms in the double bond are designated C1 and C2
cyclopropene cyclobutene cyclopentene cyclohexene
1-methylcyclohexene 1,5-dimethylcyclopentene

49. Nomenclature of cis-trans isomers
• Cis- two particular atoms (or groups of atoms) are adjacent to each
other
• Trans- the two atoms (or groups of atoms) are across from each other
Cis-2-pentene Trans-2-pentene

50. Physical Properties of Alkenes
• Cannot conduct electricity because no free moving
ions
• Boiling point and density:
―Most physical properties are similar to alkanes
―Boiling points of alkenes increases smoothly with
molecular weight
―Increased branching leads to greater volatility and
higher boiling points

51. Physical Properties of Alkenes
• Polarity:
―Relatively nonpolar
―Insoluble in water but soluble in non-polar solvent such as
hexane, gasoline, halogenated solvents and ethers
―Slightly more polar than alkanes because:
i. Electrons in the pi bond is more polarized (contributing to
instantaneous dipole moments)
ii. The vinylic bonds tend to be slightly polar (contributing to a
permanent dipole moment)

52. Chemical properties of alkenes
Combustion
(a) Complete combustion: produce CO2 + H2O
C2H4 + O2 → CO2 + 2H2O
(a) Incomplete combustion:
produce CO/C gas + H2O
C2H4 + 2O2 → 2CO + 2H2O
C2H4 + O2 → 2C + 2H2O

53. Hydrogenation
• Alkenes react with hydrogen at 180 °C at
presence of nickel/platinum (catalyst) to
produce alkanes
C2H4 + H2 C2H6
Ni, 180 °C

54. Halogenation
• No catalyst or ultraviolet is needed
• Alkenes react with halogen at room
temperature in the presence of
tetrachloromethane, CCl4
C2H4 + Cl2 → C2H4Cl2
C4H8 + Br2 → C4H8Br2
Used to test for the presence of a carbon-carbon double bond

55. Hydration
• Alkenes reacts with steam, H2O at 300 °C and
60 atm in the presence of concentrated H3PO4
(as catalyst) to produce alcohol
C2H4 + H2O C2H5OH
H3PO4
300 °C, 60 atm

56. Addition of hydrogen halides – HX
• Hydrogen halides: Hydrogen chloride, HCl or
hydrogen bromide, HBr
• Alkenes reacts with hydrogen halide, HX at
room temperature to produce haloalkane
C2H4 + HCl → C2H5Cl

57. Addition of hydroxyl group
• Alkenes react with acidified potassium
manganate(VII), KMnO4 to produce diol
compound
C2H4 + H2O + [O] → C2H4(OH)2
or
C2H4 C2H4(OH)2
KMnO4
Used to test for the presence of a carbon-carbon double bond

58. Polymerization reaction
• Small alkene molecules undergo an addition
reaction with one another at high pressure of
1000 atm and temperature 200 °C
H
H H
H C C
n
H H
C C
H H n

59. ALKYNES

60. ALKYNES
• Contain triple bond
• General formula : CnHn-2. (n=2,3,4,….)
• Two elements of unsaturated for each triple bond
• Some reactions resemble the reactions of alkenes, like
addition and oxidation
• Some reactions are specific to alkynes

61. RULES FOR NAMING ALKYNES
1. Find the longest carbon chain containing the triple
bond. This gives the parent name of the compound.
2. Change –ane ending to –yne
3. Number the chain, starting at the end closest to the
triple bond
4. Give branches or other substituents a number to
locate their position.

62. Examples
IUPAC name: pent-1-en-3-yne IUPAC name: but-1-yne-3-ol
IUPAC name: 2-methylpent-1-en-3-yne

63. THANK YOU!