The separation technique that is suitable for separating iodine from tetrachloromethane is

Analyze the question: Iodine dissolves in tetrachloromethane (CCl₄), giving a purple solution. So we need to separate a dissolved solute (iodine) from its solvent (CCl₄).

Concept:

• Solvent extraction separates a substance based on its different solubility in two immiscible solvents. Iodine could be pulled out of CCl₄ into another solvent, but that would need a suitable second solvent (e.g., aqueous KI) and is not the usual way to recover iodine from CCl₄.
• Decantation separates an insoluble solid from a liquid, or two immiscible liquids. It does not work here because the iodine is dissolved.
• Filtration separates an insoluble solid from a liquid. It does not work on a solution.
• Fractional distillation separates miscible liquids or a solution by differences in boiling points. CCl₄ boils at about 77 °C. Iodine is a solid with a much higher boiling point (about 184 °C) and also sublimes. Heating the mixture drives off the CCl₄ first, leaving the iodine behind.

Solution:

1. Iodine and CCl₄ form a homogeneous solution, so decantation and filtration are ruled out.
2. The components have very different boiling points (CCl₄ ≈ 77 °C, I₂ ≈ 184 °C).
3. Heating and distilling collects the CCl₄ as distillate, and the iodine remains in the flask.

Strictly speaking, simple distillation is the more exact term, since only one component is volatile. Among the options given, fractional distillation is the one that fits, as it is the distillation-based method.

Answer: C. fractional distillation

Tip: First ask, "Is the solid dissolved or not?" If it is dissolved, filtration and decantation are out. Then compare boiling points: a large difference points to distillation.