* Volatile impurities are substances that easily evaporate at relatively low temperatures.
* Boiling point is the temperature at which the vapor pressure of a liquid equals the surrounding atmospheric pressure.
* Impurities disrupt the intermolecular forces between the molecules of the pure substance. This disruption makes it easier for the molecules to escape into the vapor phase, lowering the overall vapor pressure.
* To reach the same vapor pressure, a lower temperature is required, resulting in a lower boiling point.
Analogy: Imagine a group of people holding hands tightly (representing the strong intermolecular forces in a pure substance). Now imagine someone trying to push their way into the group (representing a volatile impurity). The group's grip weakens, making it easier for individuals to break away (like molecules escaping into vapor).
Important Note: While volatile impurities generally lower the boiling point, there are exceptions. In some cases, the impurity might form strong interactions with the main substance, potentially leading to a higher boiling point.
Let me know if you'd like more details on specific scenarios!
