(a) isomer of n-butane is Isobutane. Its structural formula is shown below:
Isobutane

(b) Vinegar (acetic acid)

(c) 2-Propanol

(d) Ethanal

(e) Acetone

(f) Diethyl ether

These compounds together can be called organic compounds.
(g) Propanoic acid

(h) Pentan-2-ol

(i) 2,2 dibromo butane
