Organic compounds are distinct from inorganic compounds. Early scientists failed to synthesize organic compounds. Organic compounds are derived from living things. They cannot be synthesized in a laboratory known as vital force theory. This theory was rejected by Friedrich Wohler. He obtained urea ((NH2)2CO) an organic compound present in the urine of mammals.

The elements of organic compounds

  • All organic compounds contain carbon C, as an essential and important element.
  • Other than carbon, most organic compounds also contain hydrogen.
  • Other elements which may also be present include oxygen, sulfur, nitrogen, etc.

For historical and conventional reasons a few carbon-containing compounds such as Carbon monoxide, carbon dioxide, carbonates, and bicarbonates, etc. are studied in inorganic compounds.

Sources of organic compounds


It is formed by residues of trees inside the earth’s crust millions of years ago.

Natural gas

It is an important source of energy. It is a low boiling mixture of hydrocarbons. A major portion of natural gas contains methane.


Mineral oil is caused by petroleum, it is used in refined form. It is extracted from rocks as crude oil.

Classification of organic compounds

The classification of organic compounds is as follows

classificaion of organic compounds

Open chain or Acyclic compounds

This type of compound contains open chains.

  • Straight chain compounds are present in series form for example,

straight chain organic compounds

  • Branched-chain compounds are present inside by side carbon attached form

branched chain organic compounds

Closed chain compounds or cyclic compounds

These compounds contain closed chains or rings of atoms

There are two types

  • Homocyclic compound
  • Heterocyclic compound

Homocyclic compounds

The compounds in which carbon atoms form rings, homocyclic compounds rings connects are further divided as

Alicyclic compounds

Which contain a ring of 3 or more carbon atoms

alicyclic compound

Aromatic compounds

These compounds contain at least a benzene ring, six C-atoms with three alternate double or single bonds.

aromatic compounds

The aromatic compound may have a functional group or side chain.

aromatic compound

The aromatic compound may have more than one ring

aromatic compounds

Heterocyclic compounds

Compounds in which rings consist of more than one kind are called heterocyclic compounds.

For examples,

heterocyclic compounds

Major types of organic compounds

  • Carbohydrates
  • Lipid
  • Proteins
  • Nucleic acids


It is made up of carbon, hydrogen, and oxygen.

Simple carbohydrates are called sugar (Monosaccharides) for one unit. For two units it is called a disaccharide.


  • Glucose
  • Fructose
  • Sucrose


Lipids are made of Carbon, Hydrogen, Oxygen. It has higher hydrogen to oxygen ratio.


  • Cholesterol
  • Paraffin wax
  • Estrogen


Protein consists of a chain of amino acids. A protein may have a simple complexed structure.


  • Vitamin C
  • Albumin
  • Keratin

Nucleic Acids

It is a type of biological polymer made up of chains of nucleotide monomers.


  • DNA (Deoxyribonucleic acid)
  • RNA (Ribonucleic acid)

Other types of organic compounds

  • Acetaminophen
  • Acetone
  • Benzaldehyde
  • Biotin
  • Bromophenol
  • Caffeine
  • Carbon tetrachloride
  • Mustard gas
  • Vanillin

Properties of organic compounds

The physical properties include both quantitative and qualitative features

Quantitative properties

  • Boiling point
  • Melting point
  • Index of refraction

Qualitative properties

  • Oder
  • Consistency
  • Solubility
  • Colour

Classes of organic compounds

clases of organic compounds

Rules for naming organic compounds

  • First, locate the longest chain in the organic compound which has a carbon backbone. If more than two chains have equal lengths, the one with the greater number of branches should be the parent chain.
  • Identify the class of the compound and use it as a suffix.
  • In numbering for each side towards the branch the side which gives the lower number of the branch must be used. If the distance from either side is the same then use the one which gives a lower number to the 2nd branch if any on otherwise.
  • Assembly of Name: For more than one group arrange them in alphabetical order. If more than one same group is present use prefix. Use a hyphen between number and prefix.

Applications of organic compounds

  • Food industry
  • Medicines industry
  • Clothing industry
  • Synthesize plastics industry
  • Synthetic rubber industry
  • Preservation
  • Paints
  • Cosmetics
  • Textile fibers
  • Fertilizers
  • Pesticides
  • Detergents

Concept Berg

What are the properties of organic compounds?

An organic compound is a special class of chemical compounds that are carbon-containing compounds. E.g alkanes, alkenes, alcohols, phenols, etc.

Physical properties: they are Generally non-polar or partially polar and are not very soluble in polar solvents. They are further classified in different branches based on the physical behavior, i.e.

  1. Alkanes and alkenes from C1 to C4 are gases then upper members are liquids and C17 or above are solid waxes.
  2. They are a highly flammable substance
  3. Not soluble in water.
  4. Instantaneous dipoles Induced dipole forces are present in them
  5. Alkanes are odorless substances that’s why sulfur compounds are added in methane to feel its presence during leakage.
  6. Alcohols are different from them due to the presence of the OH group; they are polar substances and miscible with water.
  7. Esters on the contrary have specific smells so they have been used in fragrances and flavors.

What is an example of an organic chemical?

There are millions of organic compounds e.g. methane CH4, Ethanol C2H5OH, sugar C6H12O22.

What are the uses of organic compounds?

Organic compounds are the main source of food for animals since all plants are organic compounds. General use of organic compounds

  1. Heating purpose e.g. methane in cooking
  2. In Medicines e.g paracetamol is para acetyl phenol is an anti-inflammatory and pain reliever.
  3. Vegetable oil is mainly stearic acid and oleic acid

What organic compounds are used in medicine?

Medicines are chemical compounds that have a miracle effect like a pain killer. e.g Diclofenac sodium is a salt with amazing properties to get rid of Muscular pain. Aspirin is another example is o- salicylic acid is the most used drug for instant headache relief.

How do you know if a compound is organic?

As Name indicates organic compounds are Naturally occurring compounds and now can be synthesized in the laboratory, they have certain functional groups which are the main reason for the physical properties and chemicals reactivities.

What are the 5 main organic compounds?

Five main organic compounds are

  • Alkane (Methane)
  • Alcohols (Methanol
  • Esters (Ethanoic acid)
  • Carboxylic acid (Ethanoic Acid)

What are the 4 classes of organic compounds?

Carbohydrates, lipids, nucleic acids, and proteins are the main classes of organic compounds found in living organisms.

What are the similarities between organic and inorganic compounds?

  • Both can be synthesized in a laboratory
  • Both can contain carbon in it
  • Both are intramolecular or intermolecular interactions in it

What is meant by a functional group?

functional groups are the atoms or groups of atoms responsible for the functions of organic compounds. E.g. –OH in alcohols, C=O in carbonyl compounds

What are the properties of functional groups?

They are the main reason for the activity of these compounds. All physical and chemical properties are based upon the type of functional groups.

What functional group is COOH?

That is carboxyl group they are present in Ethanoic acid (vinegar is 5% solution of Ethanoic acid) and butyric acid Present in butter.

What is the order of acidity of different functional groups?

The acidity of organic compounds is based upon the ability to lose a proton and it depends upon the stability of its conjugate base. which may stabilize by inductive effect or resonance effect. Generally the Order of their acidity are as follows

carboxylic acids> β-dicarbonyls > mides > sulfonamides> phenols> thiols> Alcohols> Alkanes/alkenes.

What are the functional groups of sucrose?

The functional group of sucrose is, and alcohols with acetyl oxygen bridged two rings of glucose and fructose.

What is an easy way to memorize the functional groups, their structure, and their features?

The most convenient way to memorize functional groups is to practice their mechanism in chemical reactions. as we know they are the responsible sites of the organic compounds so it is based on the chemistry of organic compounds

What is the order of the boiling points of functional groups?

The boiling point depends upon the intermolecular interaction of molecules so the order of their boiling point is according to the strength of their IMA.

Proteins > Amides > Carboxylic acids > Alcohol