Question

The cis-trans nomenclature is not applicable when _________

(a) The different groups attached to the carbon atom of double bond are same

(b) Atleast one of the group attached to each carbon atom is same

(c) The different groups attached to the carbon atom of double bond are not same

(d) The cis-trans nomenclature is applicable for all compounds

The question was posed to me in an online quiz.

My question is from E and Z Nomenclature of Geometric Isomers in chapter Structure and Stereostructure of Molecules of Engineering Chemistry I

Answer 1

Right answer is (c) The different groups attached to the carbon atom of double bond are not same

Easy explanation: The cis-trans nomenclature is applicable when the different groups attached to the carbon atom of double bond are same or atleast one of the group attached to each carbon atom is same.