Functional Groups in Organic Chemistry

The longest carbon chain is the parent chain containing the principal functional group. 

The principle functional group is always given the highest priority, lowest number (1 before 2, 3, 4...), and assigned as a suffix while writing the nomenclature. Therefore, the numbering of the parent chain always starts from the principal functional group.

IUPAC, an international body engaged in developing standards for naming chemical elements and compounds, has laid several rules known as 'IUPAC rules' to identify a molecule by its parent alkane chain and the functional group. It has assigned various suffixes to identify organic chemistry's commonly seen functional groups.

Organic compounds predominantly consist of Carbon and Hydrogen atoms, also known as hydrocarbons. However, most organic compounds also contain other heteroatoms like O, N, S, and halogens as the functional group.

Out of the many ways to classify a structure, the functional group classification based on the attached atoms is listed below.

Carbon's nondiscriminatory nature to form bonds with itself and other elements has led to a wide variety of small and large organic compounds. Carbon-hydrogen compounds called hydrocarbons are mostly inert; however, carbon with other elements (N, O, S, halogen) form functional groups, the reactive part of the molecule. The functional group part of the molecule is where chemical transformations occur. Some organic compounds can have more than one functional group.

The functional group is the agent providing a molecule its quintessential character and is responsible for molecular reactivity.

It is a group of two to four atoms that connects with the rest of the molecule with a single covalent bond. Its position in a molecule can be internal or terminal.

Question- A and B are two functional isomers of compound C₃H₆O. On heating with NaOH and I₂, Isomer B forms a yellow precipitate of Iodoform whereas Isomer A does not form any precipitate. Write the formulae for A and B.

1) Functional Isomers are compounds that have same molecular formula but different functional groups. 

An Organic Compound 'A' molecular formula C₈H₁₆O₂ was hydrolyzed with dilute H₂SO₄ to give a carboxylic acid 'B' and an alcohol 'C.' Oxidation of 'C' with chromic acid also produced 'B.' On dehydration 'C' gives 1-but-ene. Write the equations for the reaction involved.

1) The first step is find out the Degree of Unsaturation (the number of double bonds or the presence of a ring) in the compound. 

The formula is,