Question

How many constitutional isomers does ${\mathrm{C}}_3{\mathrm{H}}_8\mathrm{O}$ have?

Answer 1

Constitutional Isomers

1. Constitutional isomers are isomers that share the same structural formula but have different bonding atomic organization and bonding patterns.
2. Constitutional Isomers are of three types: (a) Chain Isomers: Chain isomers are the constitutional isomers in which components of the skeleton are ordered in different ways to create different skeletal structures. Example: Pentane (${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_3$) and Neopentane (${\mathrm{CH}}_3\mathrm{CH}\left({\mathrm{CH}}_3\right){\mathrm{CH}}_2{\mathrm{CH}}_3$).
3. Positional Isomers: Positional isomers differ from each other based on the position at which the functional group is attached to the molecule. Example: Pent-1-ol (${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{OH}$) and Pent-2-ol (${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_3$)
4. Functional Isomers: They are the isomers that share the same molecular formula but vary in the manner in which the atoms are connected to each other. Example: Ethane (${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{OH}$) and Dimethyl ether (${\mathrm{CH}}_3{\mathrm{OCH}}_3$).

Constitutional Isomers of ${\mathbf{C}}_{\mathbf{3}}{\mathbf{H}}_{\mathbf{8}}\mathbf{O}$

1. ${\mathrm{C}}_3{\mathrm{H}}_8\mathrm{O}$ have three constitutional isomers. 1- Propanol (${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{OH}$)
2. 2- Propanol ${\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_3$

3. Ethyl-methyl Ether (${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{OCH}}_3$)

Therefore, ${\mathrm{C}}_3{\mathrm{H}}_8\mathrm{O}$ exhibits three constitutional isomers.