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Organic Compounds

Organic Compounds Definition

Organic compounds are a type chemical compounds where one or more than one carbon covalently bonded with each other and with other atom like nitrogen, oxygen, halogen etc. Such as, methane (CH4), ethane (C2H6), benzene (C6H6) etc.

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Few carbon containing chemical compounds like metal cyanides (CN), oxides of carbon (CO2, CO), metal carbonates (CO3) and metal carbides are inorganic compounds. Such as, sodium cyanide (NaCN), sodium carbonate (Na2CO3), calcium carbide (CaC2) etc.


Organic compounds have unique chemical and physical properties what can differ them from inorganic compounds. Such as,

  • Low boiling point
  • Low melting point
  • Low solubility in water
  • High solubility in organic solvent
  • Non conductor of electricity
  • Isomerism possible
  • Mostly covalent bonding
  • Flammable


Organic compounds can be classified in various ways. Such as, depending on sources, sizes and presence of heteroatom in organic compounds.

Natural compounds

Organic compounds are found in large number in nature and they are well known for their uses. Such as,

  • Carbohydrates- cellulose, sugar, starches etc.
  • Proteins- silk, wool, casein, in different food etc.
  • Alkaloid- quinine, morphine etc.
  • Fats and oils- cottonseed, soyabean oil, butter etc.
  • Hormones, vitamins etc.
  • Natural gas,
  • Petroleum- solvent, rubber, explosives etc.
  • Coal- drug, dyes etc.

Synthetic compounds

Organic compounds can also be made synthetically in different industries. These compounds some time exist naturally and some time they can only make synthetically. These molecules can be small or large polymer like plastics, rubber etc.


Recently biotechnology engineered molecule are synthesized in lab. Such as, insulin. These compounds are manufactured using organisms like yeast and bacteria.

Organometallic compounds

Organic compounds containing a metal atom is known as organometallic compounds.

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Structure of organic compounds

The most abundant element in organic compounds are carbon covalently bonded with each other or with other elements. Carbon has four valence electrons and the electron configuration of carbon in group state is 1s2 2s2 2px1 2py2pz0. That means it has only two unpaired electrons.

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And the electron configuration of carbon in excited state is 1s2 2s1 2px1 2py2pz1. That means it has now four unpaired electrons. Thus carbon undergoes sp3 hybridization to attach convalently with four other elements. Carbon usually attached with another carbon or hydrogen atoms, like:

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Carbon can share more than one electrons with same element to form double or triple bond. Such as:

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Carbon undergoes spor sp hybridization to form double or triple bond leaving one or two p-orbitals to participate in double or triple bonding.

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Thus the rotation around the C=C is restricted and isomerism is possible.

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Nomenclature of organic compounds

The nomenclature of organic compounds done in few steps:

Step 1:

At first the longest carbon chain are identified and named as depending on the number of carbons, like:

Number of carbons Code
1 Meth
2 Eth
3 Prop
4 But
5 Pent
6 Hex
7 Hept

Step 2:

The name of the longest chain complete with suffix -ane or other depending on functional group attached to it.

Description Code
C-C single bond only ane
C=C double bond ene
C≡C triple bond ylene
Branched  group attached with main chain yne
Alcohol anol
Aldehyde anal
Ketone anone
Carboxylic acid noic acid

Step 3:

Any name of branched alkyl group or other functional group in branched position or in longest chain can attached as prefix with the name of the organic compound.

Step 4:

The number of position of functional group or branched alkyl group must be mentioned where appropriate.


As for example: the name of following compounds contains double bonds in different positions are as follows:

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The name of compounds containing aldehyde and ketone functional groups are:

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