Freezing Point

The freezing point of a substance is the temperature at which it changes from a liquid to a solid state. This process is known as freezing. The freezing point is a characteristic property of a substance, meaning it is unique to that substance and can be used to identify it.

Factors Affecting Freezing Point

The freezing point of a substance can be affected by external factors such as pressure and impurities. In general, an increase in pressure tends to lower the freezing point of a substance, while the presence of impurities in the substance tends to raise the freezing point. This is known as freezing point depression and freezing point elevation, respectively.

Examples of Freezing Point

Water, for example, has a freezing point of 0 degrees Celsius (32 degrees Fahrenheit) at standard atmospheric pressure. However, the freezing point can be lowered by adding salt to the water, which is why salt is often used to melt ice on roads and sidewalks during winter.

Study Guide

1. Define freezing point.
2. Explain the concept of freezing point depression and freezing point elevation.
3. Give examples of substances and their freezing points.
4. Discuss the practical applications of understanding freezing points.