ALKANE

ALKANES

BY N2W2

PHYSICAL PROPERTIES OF ALKANES

• Solubility in water: • Solubility in organic
solvent:
• Alkanes is less dense than water.
• Liquid alkanes and cycloalkanes
• Alkanes and cycloalkanes are are soluble in one another, and
they generally dissolve in non-
almost totally insoluble in water polar solvents.
-they are non-polar molecule
-unable to form hydrogen bond • Good solvents for alkanes are
with polar solvent like H2O. benzene, carbon tetrachloride,
chloroform, and other
hydrocarbons.

↑ BOILING POINT OF ALKANES

DID YOU KNOW? 1) MOLECULAR WEIGHT
Most oil is generally alkanes, -as molecular weight higher/ molecular size bigger,
such as olive oil, palm oil, -strength of London forces or van der Waals force
fuel.
become stronger
At room temperature (25oC) -higher boiling point.
and atmospheric pressure (1 Mr ↑ , vdW ↑ , b.p ↑
atm), for unbranched
alkanes, 2) SURFACE AREA
-the more branches, molecule becomes more compact,
C1 – C4 : gases -surface area reduces,
C5 – C17 : liquids -this causes the branched alkanes to have a weaker van
C18 - more : solids der Waals / London forces,

-lower boiling points.
branch ↑ , s.area ↓ , vdW ↓ , b.p ↓

EXAMPLES

SCAN THIS QR CODE FOR
BETTER EXPLANATION ON
BOLING POINT OF
ALKANES

REACTION IN ALKANE

Type of reaction:
free radical substitution

Name of reaction: halogenation

FREE Initiation
RAdICAL Propagation

SuBSTITuTION
MECHANISM

Termination

https://www.youtube.com/watch?v=5HgzsltWwK8

FREE RAdICAL SuBSTITuTION MECHANISM

Initiation

Propagation

Termination

https://youtu.be/r4-
QkUtDptM