Unit 14: application of organic chemistry
C: understand the types, structures, reactions, uses and properties of isomers.
Isomers
Isomers are molecules that consist for the same molecular formulas, the same empirical formula,
however, have different atom arrangements. This further includes all other configurations by rotating
the molecules as well as around the specific bond. An example of isomers that consist of the formula
C8H10 are o-xylene, ethyl benzene, m-xylene and lastly p-xylene. There are two main types of
isomerism, which may be put in various subtypes are structural isomerism as well as stereoisomerism.
Structural isomerism
Structural isomerism arranges the atoms in a very different order. Furthermore, structural isomers
are the molecules that consist of the exact same molecular formula however structure of the atom
arrangements. Structural isomerism types include chain isomerism, position isomerism as well as
functional group isomerism.
Types of structural isomerism
Positional isomerism
Positional isomerism does not create a change to the basic carbon skeleton; however, it moves the
significant groups on the skeleton. For instance, there are two main isomers that are structural
consisting of the molecular formula C3H7Br. The one with the bromine atom on the chain at the end
as well as one in the middle of the chain.
When the model has been built, there is no way to twist one of the molecules into another.
Additionally, the bromine must be stripped off towards the end as well as reinstalled in the middle.
The hydrogen at the same time, must also be moved from the middle towards the end of the chain.
Another identical example happens with alcohols including C4H9OH.
There can be a chain isomerism mixture as well as position isomerism. So here there are two other
butanol isomers.
,Benzene positional isomers ring may be obtained. This includes the molecular formula CH7HCl. There
are 4 different isomers that may be created, depending on where the chlorine atom is positioned. In
many cases, it may also be linked to a side group carbon atom as well as there are three other
possible positions surrounding the ring. That is closer to a CH3 group, just one closer to a CH3 group
or may be opposite a CH3 group.
Functional group isomerism
Various Functional group isomers are types of structural isomerism, that belong to many compounds
facility, many homologous series). Such as the molecular formula C3H6O which may be either
propanone(ketone) as well as a propenal(aldehyde).
However, there may also be other possibilities of the exact molecular formula. This further includes
carbon-carbon double bond known as an alkene as well as an –OH group known as an alcohol, in the
exact molecule.
Additionally, other known examples include the molecular formula C3H6O2. Among its various
structural isomers are both methyl ethanoate known as an ester as well as propionic acid known as a
carboxylic acid).
Chain isomers
Chain isomers are when they share the exact same molecular formula, however the way the carbon
atoms are displaced as well as attached to each other differs for each of the isomer. Moreover, alkane
molecules that consist of 4 or more of the carbon atoms carry chain isomers. Within these isomers,
the carbon atoms attach in varies ways to be able to create the branches. For instance, butane consist
, of two isomers, C4H10. One of the isomers contain carbon atoms in a straight chain as well as the
ither consisting of a branched chain.
For instance, the structure shown below is known as a butane linear version, that is twisted around a
central carbon-carbon bond.
This structure is also used at the top.
Additionally, pentane known as C5H12 consists of three chain isomers and is an unbranched straight
chain. Other isomers branched include 2-methylbutane, which consists of one branch as well as 2,2-
dimethylpropane, which consist of two branches. There are twisted versions presented in the ones
below.
Stereoisomerism
Stereoisomerisms are the compounds that consist of the identical atoms attached, however they
differ in arrangement and structure of the atoms in space. As a result, the stereoisomers consist of
similar chemical as well as physical properties. There are two types of stereoisomerism known as
geometric(E/Z) isomerism as well as optical isomerism.