Isomerism Flashcards
Types of Structural isomerism
Ring chain, chain isomerism, position isomerism, functional isomerism, metamerism, Tautomerism
Types of stereo isomerism
Geometrical, confirmation optical
Functional pairs
- Ether (-O-) and OH
- CHO and =O
- acid and esters
- nitro and nitrite
- cyanide and isocyanide
- primary,secondary,tertiary amines
- phenolic, alcoholic (benzene ring) cpds
Stereoisomerism
Isomers having the same molecular formula and the same structural formula but differ in arrangement of atoms in space.
Geometrical isomerism
they are isomerisms which differ in configurations due to hindered rotation around the double bonds
Tautomerism
It is a phenomenon in which a single compound exists in simultaneously in two forms in equilibrium with each other and involves the simultaneous shifting of pi electrons cloud and hydrogen.
Why is the keto form stronger than the enol form?
The keto firm is more stable than the enol form due to the greater strength of carbon oxygen pi bond than carbon carbon pi bond
Meta merism
Exhibited by compounds having the same molecular formula but different number of carbon atoms on either side of the functional group
how does electronegativity depend upon hybridisation
s orbital has more electronegatiev characater
electronegativity dirreclty prop to s charact
sp>sp2>sp3
what is the 3 dimensional representation of molecules
For
example, by using solid ( ) and dashed
( ) wedge formula, the 3-D image of a
molecule from a two-dimensional picture
can be perceived. In these formulas the
solid-wedge is used to indicate a bond
projecting out of the plane of paper, towards
the observer. The dashed-wedge is used to
depict the bond projecting out of the plane of
the paper and away from the observer. Wedges
are shown in such a way that the broad end
of the wedge is towards the observer. The
bonds lying in plane of the paper are depicted
by using a normal line (—)
what is a functional group
atom/ grp of atoms joined in a specific manner which is responsible for the characteristic chemical behaviour/ properties of organic cpds.
what is a homologous series
A group or a series of organic compounds each
containing a characteristic functional group
forms a homologous series and the members
of the series are called homologues. The
members of a homologous series can be
represented by general molecular formula and
the successive members differ from each other
in molecular formula by a –CH2 unit.
Define isomers and isomerism
Two or more than two compounds having the same molecular formula but different physical/chemical or
both properties are called isomers and the phenomenon is called isomerism.
chain isomerism
when two compounds have same molecular formula, same functional group but different arrangement of carbons in the parent chain .
min C atoms for chain isomerism
min no of carbon for alkane= 4
min no of carbon for alkene= 4
min no of carbon for alkyne=5
