Concept:Certain compounds decompose or degrade if heated to their normal high boiling points. Lowering the external pressure allows them to boil at much safer, lower temperatures.
Formula:$$ P_{\text{ext}} \downarrow \implies \text{Boiling Point} \downarrow $$
Solution:- By attaching a vacuum pump to the distillation apparatus, the atmospheric pressure inside the system is drastically reduced.
- Because boiling occurs when vapor pressure equals external pressure, the liquid can reach this new, lower pressure threshold at a much lower temperature.
- This specific technique, designed to prevent thermal decomposition, is explicitly known as Vacuum Distillation.
Why other options are incorrect:Fractional distillation is for separating mixtures with close boiling points under normal pressure. Steam distillation uses steam to carry over volatile oils. Simple distillation uses standard atmospheric pressure.
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