Purple hexane layer from iodine extraction Steps:

• Halogens tested: Cl₂, Br₂, I₂; halides: Cl⁻, Br⁻, I⁻ (9 combinations total).
• Purple color in hexane indicates free I₂, which partitions from aqueous to organic layer.
• I₂ present when added directly: I₂ + Cl⁻, I₂ + Br⁻, I₂ + I⁻ (3 cases).
• I₂ produced by displacement: Cl₂ + I⁻ → I₂ + 2Cl⁻; Br₂ + I⁻ → I₂ + 2Br⁻ (2 cases).
• Total: 5 test tubes with I₂ and purple layer.

Why D is correct:

• Reactivity series (F > Cl > Br > I) predicts I₂ formation in 5 specific combinations, extracting as purple in nonpolar hexane.

Why the others are wrong:

• A: Underestimates by ignoring 4 I₂ cases (3 additions + 1 production).
• B: Underestimates by ignoring 3 I₂ cases.
• C: Underestimates by ignoring 2 I₂ cases.

Final answer: D