See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# Structural Isomers of $C_2FClBr$ **Step 1: Determine the carbon skeleton** With 2 carbons, only one possible skeleton: $C-C$ **Step 2: Identify substituents** We need to place one $F$, one $Cl$, and one $Br$ on the carbon chain. **Step 3: Analyze positions for each atom** For a 2-carbon chain ($C_1-C_2$): | Isomer | $C_1$ | $C_2$ | Description | |--------|-------|-------|-------------| | 1 | $F$ | $Cl, Br$ | F on C₁; Cl and Br on C₂ | | 2 | $F$ | $Br, Cl$ | F on C₁; Br and Cl on C₂ (same as #1) | | 3 | $Cl$ | $F, Br$ | Cl on C₁; F and Br on C₂ | | 4 | $Br$ | $F, Cl$ | Br on C₁; F and Cl on C₂ | | 5 | $F, Cl$ | $Br$ | F and Cl on C₁; Br on C₂ | **Step 4: Account for symmetry** Since $C_1$ and $C_2$ are equivalent in a 2-carbon chain, positions like ($F$ on $C_1$; $Cl, Br$ on $C_2$) = ($F$ on $C_2$; $Cl, Br$ on $C_1$). **Step 5: Count unique isomers** Five distinct structural isomers can be drawn based on different arrangements of $F$, $Cl$, and $Br$. **The answer is (B) Five**