The following two compounds are:

In which of the following is functional group isomerism $NOT$ possible?

Which type of isomerism is exhibited by acetic acid $(CH_3COOH)$ and methyl formate $(HCOOCH_3)$?

Which one of the following compounds is not an isomer of the others?

Which of the following functional groups are functional isomers of esters?

Explain the following terms:
$(a)$ Isomerism
$(b)$ Position isomerism
$(c)$ Chain isomerism
$(d)$ Functional group isomerism
$(e)$ Metamerism
$(f)$ Optical isomerism