C4H7Cl is ammonochloro derivative of C4H10 which it self exists in three ispmeric forms. (i) CH3−CH2−CH=CH2 : Its possible monochloro derivatives are: 2isomers cis and trands (2 from)CH3−CH2CH=CH−Clone isomer (one form)CH3−CH2−Cl∣C=CH2optically active (exists in two forms)CH3−Cl∣CH−CH=CH2 (ii) CH3−CH=CH−CH3 : Its possible monochloro derivatives are: (Exists in two geometrical forms)CH3−CH=Cl∣C−CH3(Exists in two geometrical forms)CH3−CH=CH−CH2Cl (iii) CH3−CH3∣C=CH2 : Its possible mono- chloro derivatives are: OnlyoneformCH3−CH3∣C=CH−Cl;OnlyoneformCl−CH2−CH3∣C=CH2 Thus, the total acyclic isomeric forms of C4H7Cl are twelve (12).