See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

Concept: Stereoisomers of disubstituted cyclohexanes include cis and trans geometric isomers, and we must check for chirality (enantiomers vs. meso forms). Step 1: Draw 1,4-dichlorocyclohexane. The two chlorine substituents are at C1 and C4 of the cyclohexane ring. Step 2: Identify possible geometric isomers. - cis-1,4-dichlorocyclohexane: both Cl atoms on the same face of the ring. - trans-1,4-dichlorocyclohexane: Cl atoms on opposite faces of the ring. Step 3: Check chirality of each isomer. - cis-1,4-dichlorocyclohexane: C1 and C4 each bear Cl, H, and two ring carbons. Due to the symmetry plane passing through C1 and C4 (bisecting the ring), the molecule is achiral (it has an internal plane of symmetry). It is a meso-like compound — one stereoisomer, not a pair of enantiomers. - trans-1,4-dichlorocyclohexane: Similarly, the molecule has a plane of symmetry (through C1 and C4), making it achiral as well. It exists as one achiral form. Step 4: Count total stereoisomers. - cis isomer: 1 stereoisomer (achiral) - trans isomer: 1 stereoisomer (achiral) - Total = 2 stereoisomers Step 5: Why other options fail. - (a) 0: Incorrect; there are distinct cis and trans forms. - (b) 1: Incorrect; both cis and trans forms exist as separate stereoisomers. - (d) 4: Incorrect; this would imply each geometric isomer is chiral and exists as enantiomeric pairs, but both isomers have planes of symmetry and are achiral. Therefore, the correct answer is C.