Position isomerism:
It is due to the difference in the position of the substituent atom or group or an unsaturated linkage in similar carbon chain.
A. Carboxylic, aldehydes acids and cyanides do not depict position isomerism.
B. Monosubstituted alicylic elements and aromatic substance do not depict position isomerism.
C. Structural isomers that differ in the position of the functional group are known as regiomers.