2. Organic chemistry is the study of the structure,
properties, composition, reactions, and preparation of
carbon-containing compounds. Most organic
compounds contain carbon and hydrogen, but they may
also include any number of other elements (e.g.,
nitrogen, oxygen, halogens, phosphorus, silicon,
sulfur).
3. The compounds in solid, liquid or gaseous states which
contain carbon in their molecule are known as organic
compounds.
There are a large number of organic compounds and
therefore a proper systematic classification was
required.
Organic compounds can be broadly classified as
acyclic (open chain)
cyclic (closed chain).
4. It was assumed that organic compounds are produced
by living organisms due to the presence of Vital
Force.
This theory remained unchallenged and no one ever
even made effort test this in lab.
In 1828, Germen Chemist Friedrich Wohler
derived first organic compound from inorganic
compound in lab.
He basically reacted Ammonium cyanate and
obtained urea.
Urea obtained in this way was identical in all respects
to the urea obtained from urine.
5.
6. Organic Compounds Classification
Moving on to their classification in detail:
7. These compounds are also known as aliphatic
compounds, they have branched or straight chains.
Following are the examples in this category.
8. These are cyclic compounds which contain carbon
atoms connected to each other in a ring (homocyclic).
When atoms other than carbon are also present then it
is called heterocyclic. Examples of this type are as
follows:
9. They are a special type of compound which
contains benzene and other ring related compounds.
Similar to alicyclic, they can also have heteroatoms in
the ring. Such compounds are called heterocyclic
aromatic
(a) Benzenoid aromatic compound
Some examples are as follows:
11. Low melting points
Low boiling points
Low solubility in water
High solubility in nonpolar solvents
Flammable
Solutions are nonconductors of electricity
Exhibit covalent bonding
Exhibit isomersim
Chemical reactions are slow
12. Hydrocarbons
All organic compounds that are entirely made up of
only two kinds of atoms, carbon and hydrogen.
Typically, hydrocarbons are colorless gases that have
very weak odors.
Hydrocarbons can feature simple or relatively complex
structures and can be generally classified into four
subcategories, namely alkanes, alkenes, alkynes, and
aromatic hydrocarbons.
13. The study of hydrocarbons can provide insight into the
chemical properties of other functional groups and their
preparation.
Furthermore, hydrocarbons such as propane and butane
are used for commercial fuel purposes in the form of
Liquefied Petroleum Gas (LPG).
Benzene, one of the simplest aromatic hydrocarbons,
serves as the raw material for the synthesis of many
synthetic drugs
14. Saturated Hydrocarbons:
In these compounds, carbon-carbon atoms and carbon-
hydrogen atoms are held together by single bonds. These
single-bonded compounds are the simplest hydrocarbons.
These types of hydrocarbons don’t have double or triple
bonds. In terms of hybridization, they have
Sp3 hybridised carbon atoms with no Sp2 or Sp
hybridised carbon atoms. They are together called
alkanes which have a general formula of CnH2n+2. For
example, CH4 andC 3H 6.
15. Unsaturated Hydrocarbons: These compounds consist
of a single, double or triple bond between carbon-carbon
atoms. The double-bonded compounds are called
alkenes, and the triple-bonded compounds are called
alkynes. The general formula for alkenes is CnH2n, and
for alkynes, the general formula is CnH2n-2.
Cycloalkanes: These hydrocarbons possess one or
multiple carbon rings. The hydrogen atom is attached to
the carbon ring.
.
16. Aromatic Hydrocarbons:
They are also called arenes. Arenes are compounds
which consist of at least one aromatic ring.
Aliphatic Hydrocarbons:
They are straight chain structures having no rings in
them.
Alicyclic Hydrocarbons:
They are hydrocarbons having a ring structure in
them. The carbons atoms can be Sp, Sp2, or
Sp3 hybridised
17. The term molecule refers to very large molecules and
something that consists of more than one atom. Herman
Staudinger coined it in 1920. Macromolecules are so
huge that these are made up of more than 10,000 or
more atoms.
18. Macromolecules are also termed as polymers. They are
formed by the polymerization of molecules such as
carbon, hydrogen and oxygen.
The monomer units of macromolecules are polar in
nature, with their heads and tails with different physical
and chemical properties.
19. There are three main types of biological
macromolecules, according to mammalian systems:
Carbohydrates
Nucleic acids
Proteins
Lipids
20. Carbohydrates
Carbohydrates are polymers of carbon, hydrogen and
oxygen. They can be classified as monosaccharides,
disaccharides and polysaccharides. Carbohydrates are
found in starch, fruits, vegetables, milk and sugars.
They are an important source of a healthy diet.
21. Nucleic Acids
The nucleic acids include DNA and RNA that are the
polymers of nucleotides. Nucleotides comprise a
pentose group, a phosphate group, and a nitrogenous
base group. All the hereditary information is stored in
the DNA. The DNA synthesized into RNA and
proteins.
22. Proteins
Proteins are the polymers of amino acids. These
include the carboxylic and the amino group. There
would be no lipids or carbohydrates
without proteins because the enzymes used for their
synthesis are proteins themselves.
23. Lipids
Lipids are a hydrophobic set of macromolecules, i.e.,
they do not dissolve in water. These involve
triglycerides, carotenoids, phospholipids, and steroids.
They help in the formation of the cell membrane,
formation of hormones and in the and as stored fuel.
