The Boiling Point of Water and Impurities

What does it mean if a certain sample of water boils at a higher temperature than the boiling point of pure water?

Provide a reason for your answer.

Answer:

The sample of water is impure, as evidenced by its higher boiling point than the boiling point of pure water.

When a certain sample of water boils at a temperature higher than the boiling point of pure water, it indicates the presence of impurities in the water. These impurities can be in the form of dissolved solids, gases, salts, minerals, or other substances that are not typically found in pure water.

The boiling point of a liquid is the temperature at which its vapor pressure equals the pressure of the surrounding environment. In the case of water, the boiling point is 100°C at sea level under normal atmospheric pressure. However, when impurities are introduced into the water, they disrupt the homogeneous nature of the liquid and raise the boiling point.

Impurities in water cause the boiling point to increase because they interfere with the transition of water molecules from the liquid state to the gaseous state. This disruption requires the water to be heated to a higher temperature in order for it to reach the vaporization point.

Therefore, if a sample of water boils at 101.5°C instead of the standard 100°C, it is a clear indication that the water is impure and contains substances that raise its boiling point. This information can be used to assess the quality and purity of the water sample.