Download - Topic 6 - Introduction - Alkanes
What are Hydrocarbons?What are Hydrocarbons?
• A A hydrocarbonhydrocarbon is a molecule which is a molecule which contains only the elements contains only the elements CarbonCarbon and and Hydrogen.Hydrogen.
• Hydrocarbons are obtained from the Hydrocarbons are obtained from the FractionalFractional DistillationDistillation of crude oil. of crude oil.
• We use them for We use them for fuelsfuels in cars in cars (octane) and in cookers (methane). (octane) and in cookers (methane).
Hydrocarbons Hydrocarbons
•Homologous SeriesHomologous Series• a group of chemically similar compounds a group of chemically similar compounds
which can be represented by a general which can be represented by a general formula. formula.
• Physical properties change gradually through Physical properties change gradually through the series the series
• Alkanes Alkanes
• AlkenesAlkenes
• CycloalkanesCycloalkanes
AlkanesAlkanes
• MethaneMethane MonstersMonsters• EthaneEthane Eat Eat • PropanePropane PupilsPupils• ButaneButane ButBut• PentanePentane PreferPrefer• HexaneHexane HairyHairy• HeptaneHeptane HaggisHaggis• OctaneOctane oror• NonaneNonane Nice Nice • DecaneDecane DinnersDinners
Alkanes - MethaneAlkanes - Methane
• 3D Full Structural 3D Full Structural 2D Full 2D Full Structural Structural
Formula Formula FormulaFormula
AlkanesAlkanes
• Each member can be represented in Each member can be represented in three different ways:three different ways:
MethaneMethane PropanePropane• Full Structural Full Structural
Formula Formula • Shortened Structural Shortened Structural
FormulaFormula• Molecular FormulaMolecular Formula
AlkanesAlkanes
• The Alkanes are a family of The Alkanes are a family of hydrocarbons and all share the hydrocarbons and all share the same chemical properties:same chemical properties:• Single Carbon to carbon bonds ( - C – Single Carbon to carbon bonds ( - C –
C - )C - )• All end in -‘ane’All end in -‘ane’• Saturated hydrocarbonsSaturated hydrocarbons• All share a General Formula All share a General Formula
AlkanesAlkanes
AlkaneAlkane
(Carbon (Carbon Atoms)Atoms)
MoleculaMolecular Formular Formula
Shortened Shortened Structural Structural FormulaFormula
Full Full Structural Structural FormulaFormula
Boiling Boiling
PointPoint
MethaneMethane
(1)(1)-164-164
EthaneEthane
(2)(2)CC22HH66 CHCH33CHCH33 - 89- 89
PropanePropane
(3)(3)
AlkanesAlkanes
AlkaneAlkane
(Carbon (Carbon Atoms)Atoms)
MoleculaMolecular Formular Formula
Shortened Shortened Structural Structural FormulaFormula
Full Full Structural Structural FormulaFormula
Boiling Boiling
PointPoint
MethaneMethane
(1)(1)CHCH44 CHCH44 -164-164
EthaneEthane
(2)(2)CC22HH66 CHCH33CHCH33 - 89- 89
PropanePropane
(3)(3)CC33HH88 CHCH33CHCH22CHCH33 - 42- 42
AlkanesAlkanes
AlkaneAlkane
(Carbon (Carbon Atoms)Atoms)
MoleculaMolecular Formular Formula
Shortened Shortened Structural Structural FormulaFormula
Full Full Structural Structural FormulaFormula
Boiling Boiling
PointPoint
ButaneButane (4)(4)
PentanePentane
(5)(5)
HexaneHexane
(6)(6)
AlkanesAlkanes
AlkaneAlkane
(Carbon (Carbon Atoms)Atoms)
MoleculaMolecular Formular Formula
Shortened Shortened Structural Structural FormulaFormula
Full Full Structural Structural FormulaFormula
Boiling Boiling
PointPoint
ButaneButane (4)(4)
CC44HH1010 CHCH33CHCH22CHCH22
CHCH33
-1-1
PentanePentane
(5)(5)CC55HH1212 CHCH33CHCH22CHCH22
CHCH22CHCH33
3636
HexaneHexane
(6)(6)CC66HH1414 CHCH33CHCH22CHCH22
CHCH22CHCH22CHCH33
6969
AlkanesAlkanes
AlkaneAlkane
(Carbon (Carbon Atoms)Atoms)
MoleculaMolecular Formular Formula
Shortened Shortened Structural Structural FormulaFormula
Full Full Structural Structural FormulaFormula
Boiling Boiling
PointPoint
HeptaneHeptane
(7)(7)
OctaneOctane
(8)(8)
AlkanesAlkanes
AlkaneAlkane
(Carbon (Carbon Atoms)Atoms)
MoleculaMolecular Formular Formula
Shortened Shortened Structural Structural FormulaFormula
Full Full Structural Structural FormulaFormula
Boiling Boiling
PointPoint
HeptaneHeptane
(7)(7)CC77HH1616 CHCH33CHCH22CHCH22
CHCH2 2
CHCH22CHCH22CHCH33
9898
OctaneOctane
(8)(8)CC88HH1818 CHCH33CHCH22CHCH22
CHCH2 2
CHCH22CHCH22CHCH33
126126