Question

Write the structural formulae of all the isomers of hexane.

Answer 1

Hint Isomer is generally made up of two words iso + mer where iso means equal and mer means many parts and this is basically a Greek word. Hence isomer is defined as that molecule which has the same molecular formula but a different arrangement of atoms.

Complete Step by step solution:
Hexane is basically an alkane i.e. the bonds present in hexane are single bonds. It is represented by the chemical formula ${{C}_{6}}{{H}_{14}}$.
Hence isomers are those compounds which have the same molecular formula but a different arrangement of atoms and there are mainly five types of isomers present in hexane which can be considered as follows:
1. Hexane, it is a long straight chain of six carbon atoms which can be shown as: $C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}C{{H}_{2}}C{{H}_{2}}C{{H}_{3}}$
2. Isohexane which also known by the name 2-methyl pentane in which there is a chain of 5 carbon atoms and one methyl group is attached on 2nd position of the five-carbon chain and it can be represented as: $C{{H}_{3}}CH(C{{H}_{3}})C{{H}_{2}}C{{H}_{2}}C{{H}_{3}}$
3. 3-methylpentane this isomer contains five carbon long chain in which one methyl group is attached at 3rd position of chain and can be shown as: $C{{H}_{3}}C{{H}_{2}}CH(C{{H}_{3}})C{{H}_{2}}C{{H}_{3}}$
4. 2,3-dimethylbutane in this isomer longest chain is 4 carbon atoms which have two methyl groups on the position 2nd and 3rd of the chain and can be shown as: $C{{H}_{3}}CH(C{{H}_{3}})CH(C{{H}_{3}})C{{H}_{3}}$
5. Neohexane was also known by the name 2,2-dimethylbutane which is four-carbon chain having 2 methyl groups on 2nd position of 4 membered chains and can be shown as: $C{{H}_{3}}C{{(C{{H}_{3}})}_{2}}C{{H}_{2}}C{{H}_{3}}$
Hence hexane has five isomers.

Note: Hexane is a nonpolar molecule having weak intermolecular interactions between the molecules of pure liquid and hydrocarbons. Hexane is used as common solvents in synthetic reactions and in inks or adhesives etc.