Glycrine can be purified by

Options

A. vacuum distillation
B. simple distillation
C. steam distillation
D. fractional distillation

Answer

**Step-by-Step Text Solution:**

1. **Understanding Glycerin:**
- Glycerin, also known as glycerol, is a compound with the molecular formula C3H8O3. It contains three hydroxyl (–OH) groups, making it a triol.

2. **Boiling Point of Glycerin:**
- Glycerin has a high boiling point of 290°C. This high boiling point is significant because it influences the choice of purification method.

3. **Purification Techniques:**
- The question presents four methods of purification:
- **Vacuum Distillation:** Used for compounds with high boiling points to prevent decomposition.
- **Simple Distillation:** Suitable for separating two liquids with a significant difference in boiling points.
- **Steam Distillation:** Ideal for temperature-sensitive substances, allowing separation below their decomposition point.
- **Fractional Distillation:** Used for separating two miscible liquids through repeated distillation and condensation.

4. **Choosing the Right Method:**
- Given glycerin's high boiling point, simple distillation would not be effective as it may lead to decomposition.
- Steam distillation is not suitable since glycerin is not temperature-sensitive in the context of decomposition.
- Fractional distillation is also not appropriate as glycerin is not being separated from another miscible liquid.
- Therefore, the most suitable method for purifying glycerin is **vacuum distillation**. This method allows for the purification of glycerin without reaching its decomposition temperature.

5. **Conclusion:**
- The correct answer for purifying glycerin is **vacuum distillation**.

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