Read the following statements carefully: (I) Steam distillation is used to purify substances which are steam volatile and miscible with water. (II) Distillation under reduced pressure is used to purify liquids having very high boiling points and those which decompose at or below their boiling points. (III) A fractionating column provides many surfaces for heat exchange between the ascending vapours and the descending

Step-by-step solution

Statement (I) is incorrect because steam distillation is applied to separate substances which are steam volatile and are immiscible with water, not miscible. Statement (II) is correct as distillation under reduced pressure (vacuum distillation) lowers the boiling point, preventing decomposition of high-boiling liquids. Statement (III) is correct because the fractionating column provides a large surface area for repeated vaporization and condensation, facilitating the separation of close-boiling liquids. Statement (