How many total structural isomers are possible for the molecular formula ? — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

First, compute the Degree of Unsaturation: $DU = (2 + 1) - \frac{4 + 2}{2} = 3 - 3 = 0$. The compound is saturated and acyclic with a two-carbon chain. Distributing two chlorine atoms across two carbons gives only two unique structural possibilities: both chlorines on the same carbon (1,1-dichloroethane) or one chlorine on each carbon (1,2-dichloroethane). Total structural isomers = 2.