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Physical Properties of Organic Compounds
PROPERTIES
TYPES
Alkanes
Aliphatic
Aromatic
Alkenes
Aliphatic
Aromatic
Arenes
Benzene
Halogen Derivatives
Haloalkanes
Haloarenes
Arenes
CH3
EXAMPLE
NOMENCLATURE
H3C
CH3
CnH2n+2
~e
H2C
CnH2n
Cyclo~e
 in Mr = More e
= more id-id
*Branching  bp
Branched isomer
has lower surface
area than
straight-chain
isomer = lower
id-id interactions.
–
BOILING POINT
Higher bp
than corr.
aliphatic
alkanes
CH3Cl
CnH2n
CnH2n–2
Presence of cis
and trans isomer
es with
es with g C
CH2
g
C
Similar bp as
alkane with same
number of C
*bp may be
slightly higher for
cis isomers as
the dipole
moment do not
cancel out = pdpd interactions 
Higher bp
MELTING POINT
SOLUBILITY
(POLAR SOLVENTS)
SOLUBILITY
(NON POLAR SOLVENTS)
DENSITY
Higher bp
than corr.
aliphatic
alkenes
(WRT WATER)
Variable
Higher bp than
6C alkane (69°C)
and 6C alkene
(63.5°C).
Comparable bp
with cyclohexane
(81°) and
cyclohexene
(83°C).
5.5°C
Higher mp
than corr.
aliphatic
alkanes
es with g C
Trans–isomers
pack better into a
regular lattice i.e.
higher bp than
cis-isomers.
Higher mp
than corr.
aliphatic
alkenes
Insoluble
Insoluble
Soluble (CCl4)
Soluble
Less Dense
Less Dense
C6H6
Phenyl~
80°C
es with g C
M.P affected by
how close the
molecules can
pack together
Branchg may 
mp
Though less
efficient id-id
forces, isomer
able to pack into
regular arrays
(Denser than
aliphatic alkanes)
Cl
Higher mp than
6C alkane (–
95°C) and 6C
alkene (–138°C).
Comparable mp
with cyclohexane
(6.5°).
Has higher mp
than cyclohexene
(–104°C)
Dependent on e–
cloud size
(molecular weight)
CnH2n+1X
Higher bp than
corr. alkanes due
to larger Mr.
(for some also
due to presence
of pd-pd)
Bp es
-with size of X.
Effect of id-id
forces outweigh 
polarity of bond
i.e weaker pd-pd
-with more subsn
of X
Dependent on
molecular weight
and shape.
For isomers, 1,4usually has the highest
mp compared to 1,2and 1,3-. More
symmetrical molecular
fits better into crystal
lattice.
Insoluble
Soluble
(acts as solvent)
C6H5X
Higher mp
than corr.
alkanes due
to larger Mr.
Comparable bp
to corr. alkyl
halides i.e higher
bp than corr.
alkanes
Comparable mp
to corr. akyl
halides i.e higher
bp than corr.
alkanes
Insoluble
(unable to form H bondg with water)
Soluble
Less Dense
Less Dense
(Denser than
aliphatic alkenes)
Less Dense
Less Dense
Denser
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Physical Properties of Organic Compounds
PROPERTIES
TYPES
Hydroxy Compounds
Alcohols
Phenols
Carbonyl Compounds
Aldehydes
Ketones
OH
EXAMPLE
NOMENCLATURE
BOILING POINT
MELTING POINT
SOLUBILITY
(POLAR SOLVENTS)
SOLUBILITY
(NON POLAR SOLVENTS)
DENSITY
(WRT WATER)
H
CnH2n+1OH
CnH2n+2O
Much higher
than
correspong
alkanes.IMF H
bondg.
Lower alc are
liquids at room
temp till 12C
Factors
*Length of Alkyl
Chain (id-id)
*Branching
R
C
CH3OH
C6H5OH
182°C
Higher than
hexanol (156.5°C)
O
O
C
O
R
R
~al/formyl~
~one/oxo~
Polar compds. Higher bp than
non-polar compds of similar
M r.
Lower bp than acid and alc.
because no H bonding
Much higher
than
correspong
alkanes.
41°C
Higher than
hexanol (–52°C)
Lower alc are
soluble. Solubility
 as C  due to 
h.phobic nature
Partially soluble in rt
due to H bg but has big
h.phobic ring. Solubility
is enhanced by heating
or addition of alkali.
Carboxylic Acid & Derivatives
Carboxylic A. A. Derivatives
Polar compds. Higher mp than nonpolar compds of similar Mr.
Lower mp than acid and alc.
because no H bonding
RCOOH
H3C
~oic acid
Cl
~yl chloride
Higher bp due to
H bonding in
polar compd.
Stronger than
alcohol because OH is more
polarized
(presence of e–
carbonyl groups)
Higher mp due to
H bonding in
polar compd.
Branching & packing affects mp too.
Lower aldehydes and
ketones are soluble in water,
ability to form H bonding with
water
C
ethanoyl chloride
Lower acids
are soluble in
water
Nitrogen Compounds
Amines
Amides
O
R
N
R
R
C
N
R
R
R
~amine/
1°: ~oic acid ~amide
2°: alkyl on N as sub.
amino~
Acid chlorides:
Lower bp wrt to
carboxylic acid
because of its
inability to form H
bonding.
Acid amides:
Has –NH2 group
and posses IM H
bonding. Higher bp.
Acid chlorides:
Polar, no H Bg
Acid amides:
Polar, H Bg
Acid derivat.s:
depend on size
Amides & Acid
Chloride: soluble
Polar compds
(ex 3°) can H
Bondg. Higher
mp than nonpolar compds of
similar Mr but
lower than alc
and carboxylic
acid.
High bp due to H
bondg, usually
higher than corr
carboxylic acids.
(1° or 2°)
Higher mp than
non-polar
compds of
similar Mr but
lower than alc
and carboxylic
acid.
High mp due to H
bondg, usually
higher than corr
carboxylic acids.
Lower amines
are soluble due
to H Bondg
Lower amides are
soluble due to H Bondg
Soluble (solubility decreases with increasing C for all these compounds)
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