Open In App

Organic Chemistry – Some Basic Principles and Techniques

Last Updated : 11 Oct, 2022
Like Article

Organic Chemistry is the branch of science that deals with the study of the structure, properties, composition, and reaction of hydrocarbons and their derivatives. It is the science of organic compounds and it started about 200-225 years ago. It is the branch of chemistry that deals with the scientific study of organic compounds (compounds that contain covalently bonded carbon atoms). In this, the structure and chemical composition, physical and chemical properties, and chemical reactions of these hydrocarbons are studied. Carbon forms bonds with itself and with other elements or compounds to form long chains of hydrocarbons. E.g. Methane (CH4) and Ethane (CH3-CH3).

Structural Representation of Organic Compounds

Organic chemistry focuses on the highlights, qualities, composition, and responses of natural compounds. Carbon and hydrogen are present in most organic compounds along with some other elements, for instance, nitrogen, oxygen, halogens, phosphorus, silicon, and sulfur. In this compound, carbon is the main element and other elements are supplementary. The compounds obtained from plants and animals were termed organic to indicate their source was a living organism.

Complete Structural Formula

The full/complete structural formula shows all the atoms in a molecule, the types of bonds that bind them and how are they interconnected. The two-electron covalent link may be simply represented in Lewis structures with a single dash. Such a structural formula emphasizes the electrons involved in the creation of the bonds. For example, a single dash denotes a single bond, a double dash denotes a double bond, and a triple dash denotes a triple bond. On heteroatoms like oxygen, halogens, and others, lone pairs of electrons may or may not be visible. 

Condensed Structural Formula

The condensed structural formula is used to save space, and effortlessly reduced and used as condensed structural formulas. It is the shortened version of full structural formulas that are created by removing part or all of the dashes that stand in for covalent bonds. Similar repeated units are enclosed in parenthesis and their repetition is denoted by subscripts. For instance, CH3CH2CH2CH2CH2CH3 can be further compressed to CH3(CH2)4CH3. In condensed structural equations, parenthesis plays a crucial function. By enclosing the repetitive structural unit in brackets and adding an integer as a subscript to represent the number of repetitions, we may further compress these structural formulas.

Bond Line Structural Formula

A bond-line structure is a more organized drawing than a condensed structural formula. However, to understand the simplified bond-line structure, one has to add many features to comprehend the overall structure. Carbon and hydrogen atoms are not displayed in a bond line structural depiction, and the lines denoting carbon-carbon bonds are drawn in a zigzag pattern. In the bond line format, only heteroatoms are written. Unless a functional group specifies otherwise, the terminals in bond-line structures represent methyl (CH3) groups, and the line junctions represent carbon atoms bound to the precise amount of hydrogen molecules needed to meet the carbon atoms’ valency requirements. 

Classification of Organic Compounds

Organic compounds are classified into two types based on the structure of the carbon chain, i.e. Open chain compounds and cyclic or closed-chained compounds. To put it another way, the classification is done on the basis of the arrangement of carbon atoms in their structure.

Open Chain Compounds

These are compounds with a linear structure, rather than a cyclic one. An open-chain compound having no side chain is called a straight chain compound and an open-chain compound in which a side chain is present is called a branched chain compound. All the branched chain and open chain compounds that contain no rings in them are aliphatic. 

Closed Chain Compounds

These are compounds in which one or more series of atoms in the compound are connected to form a ring. They are further subdivided into two types i.e. Homocyclic compounds and Heterocyclic compounds. Homocyclic compounds are compounds in which atoms are of the same chemical elements. Heterocyclic compounds are compounds containing atoms of at least two different elements. Homocyclic compounds are further categorized into two groups i.e. Alicyclic compounds and Aromatic compounds. The alicyclic compound contains one or more carbon rings which may be either saturated or unsaturated, but do not persist in any aromatic character. An aromatic compound is any of a large class of unsaturated chemical compounds characterized by one or more planar rings of atoms joined by covalent bonds of two different kinds. 

Nomenclature of Organic Compounds

The nomenclature of Organic compounds follows the recommendations of the International Union of Pure and Applied Chemistry in naming organic compounds, carbocations, etc. IUPAC formulate rules and methods for naming organic compounds based on their structural formula. Chemical nomenclature is based primarily on naming a presumed geometrical arrangement of atoms. The approach of IUPAC is to present rules for derivate names for compounds systematically. All derivations, either multiple bonds or atoms other than carbon and hydrogen, are indicated by prefixes or suffixes according to a specific set of priorities.

The choice and naming of a parent structure come first in the process of creating a systematic name for an organic molecule. Prefixes, infixes, and, in the case of a parent hydride, suffixes that express precisely the structural modifications necessary to produce the compound in question from the parent structure may then be added to this basic name. There are traditional names that are popularly used in both business and academia, as opposed to such systematic names. Acetic acid, benzene, and pyridine are a few examples. Therefore, these traditional names are kept when they satisfy the standards of utility and when they conform to the overall pattern of systematic naming.

Organic Chemical Reaction Mechanism 

There are quite a few common electron displacement effects in substrate molecules: it is a long-lasting effect that develops whenever an electron-withdrawing group or an electron-giving group is joined to a chain of singly linked carbon atoms. The inductive effect, also known as the I effect, is the displacement of sigma-electrons along a saturated carbon chain as a result of the presence of an electron-withdrawing group or an electron-repelling group at one end of the chain, which leads to the development of partial positive or partial negative charges in decreasing order of magnitude.

The Shapes of Carbon Compounds 

Tetravalent carbon atom is the building block of structural organic chemistry. Tetravalent means it can form four bonds and its valency is four. Carbon follows the octet rule and forms four bonds with other elements or other carbon atoms. This is referred to as carbon tetravalency. The four hydrogen atoms, with four carbon atoms, form a structure known as a tetrahedron. 

Functional Groups 

A functional group is a group of atoms or bonds within a substance that is responsible for the substance’s distinctive chemical reactions. These groups were introduced as a useful method for maintaining these numerous compounds because chemical reactions occur in the functional group and compounds with the same functional group undergo similar reactions. 

Homologous series

In this series, a group of carbon compounds are represented by general formula (e.g. alkanes – CnH2n+2) and have similar chemical properties. Every succeeding member differs from the previous one in this series. 

Importance of Organic Chemistry 

Organic chemistry plays an important role in our everyday life, and its importance in the present scenario has increased immensely compared to its inception. The study of organic chemistry is required by chemists and pharmacists for the synthesis of medicines. The food, paper, clothing, soap, perfumes, and medicines used on a daily basis are all organic compounds. The field of organic compounds has helped mankind in numerous ways, such as the synthesis of several drugs, polymers, and other natural products. Synthetic organic chemistry is one of the important applications of organic chemistry that deals with the study of the design and construction of organic compounds for practical implementation. It is also essential for understanding basic biochemical principles.


Organic chemistry is essential in discovering new drug-candidate molecules for the treatment of innumerous amount of diseases. For example – Aspirin is used as a medication to cure migraine and Ibuprofen is a pain reliever, both are natural mixtures. 


The role of organic chemistry in enhancing the flavour of food and developing the taste. It has an important role as people tend to go for tastier meals. Organic preservative work by draining out the liquid from the food substance and increasing the shelf life. For example – Starch which is sugar is a natural compound and a constituent of rice and different grains. 


In the textile industry, organic chemistry is also much used. The most expensive fibre is produced from silk caterpillar and Nylon, Polyester, and Cotton used in the fabric of the cloth are types of natural compounds. 


The fossil fuels, coal, petroleum, and natural gas consist primarily of hydrocarbons and are important in everyday life. For example – Gasoline, Petrol, and Diesel are natural mixtures utilized in the car business on a large scale. 

FAQs on Organic Chemistry

Question 1: What is meant by organic compounds? 


Organic compounds are one of a large class of chemical compounds in which one or more carbon atoms are covalently paired with other elements, other carbon atoms or other common atoms like hydrogen, oxygen, or nitrogen. Organic compounds example are benzoic acid, aromatic compounds, benzoic aldehyde, propanoic acid, butanoic acid, malonic acid, amines, diethyl malonate, etc. 

Question 2: What are the uses of organic compounds?


Organic molecules are utilized in various aspects in human culture including food, drugs, fills, etc. These compounds are necessary for meeting our basic needs of clothing (fabric like nylon, cotton, silk, etc), health (Many medicines are manufactured based on the principles of organic chemistry), Propane, octane, and methane are various form of alkanes and is used as fuel in the vehicle and warming/cooking oil in the home. 

Question 3: Name some organic compounds that are used in medicine. 


Compounds used as medicinal products are mostly organic compounds. For example- Paracetamol is list of organic chemicals, it is used as analgesic drug. Aspirin or acetyl salicylic acid is an analgesic-antipyretic drug. Antalgin or Methampyron is also part of analgesic-antipyretic drugs used for reducing pain. Sulfadiazine is an anti-bacterial drug used for the treatment of rheumatic fever.

Question 4: Why are organic compounds essential? 


Organic compound are fundamental as they are present in every living entity. In every living organism carbon is present.  These compounds are essential parts that move the world in considerable amount of cycle. For example, the carbon cycle that includes the exchange of carbon atoms between plants and animals during photosynthesis and cellular respiration. 

Question 5: Which elements are present in organic compounds? 


There are four major elements i.e. hydrogen, carbon, oxygen and nitrogen which are used to form most of the organic compounds. In this compounds carbon is covalently linked to other elements or carbon itself forming a stable structure. Apart from this phosphorous, sulfur, silicon, and the halogens is also used to form organic compound with carbon. 

Like Article
Suggest improvement
Share your thoughts in the comments

Similar Reads