Question

A liquid compound (x) can be purified by steam distillation only if it is

• A. Steam volatile, immiscible with water
• B. Not steam volatile, miscible with water
• C. Steam volatile, miscible with water
• D. Not steam volatile, immiscible with water

Answer 1

The Correct Option is A

To determine which liquid compounds can be purified by steam distillation, we must understand the principles behind the process of steam distillation:

1. Steam distillation is a technique used to purify or separate temperature-sensitive compounds that are volatile in the presence of steam.
2. For a compound to be effectively purified by steam distillation, it should be steam volatile and immiscible with water.
3. Being steam volatile means the compound has the ability to vaporize with steam at a temperature lower than its usual boiling point.
4. Immiscibility with water ensures that the compound can be separated from water, as they will form separate layers upon condensation.

Given the above conditions, let's evaluate the options:

• Option 1: Steam volatile, immiscible with water—This meets both criteria for steam distillation: volatility with steam at lower temperatures and immiscibility with water, making it the correct choice.
• Option 2: Not steam volatile, miscible with water—This option is incorrect because if a compound is not steam volatile, it cannot be distilled with steam.
• Option 3: Steam volatile, miscible with water—Although steam volatility is present, miscibility with water means it won't separate out effectively after condensation.
• Option 4: Not steam volatile, immiscible with water—Even though it is immiscible with water, the lack of steam volatility makes steam distillation ineffective.

Therefore, the correct answer is that a liquid compound (x) can be purified by steam distillation if it is Steam volatile, immiscible with water.