Sublimation

Sublimation is the process in which a solid substance transitions directly into a gas without passing through the liquid phase. This occurs when the vapor pressure of the solid substance exceeds the atmospheric pressure at a given temperature.

Key Concepts

1. Phase Transition: Sublimation is a type of phase transition, where a substance changes from a solid to a gas without becoming a liquid.
2. Energy Transfer: Sublimation involves the absorption of heat energy, as the solid gains enough energy to break its intermolecular bonds and enter the gaseous phase.
3. Examples: Common examples of substances that undergo sublimation include dry ice (solid carbon dioxide), mothballs (naphthalene), and frozen carbon dioxide snow.
4. Endothermic Process: Sublimation is an endothermic process, meaning it requires heat energy input to occur.

Study Guide

When studying sublimation, it's important to understand the following key points:

1. Define sublimation and distinguish it from other phase transitions like melting and vaporization.
2. Understand the concept of vapor pressure and how it relates to sublimation.
3. Identify common substances that undergo sublimation and their applications in daily life and industry.
4. Explain the role of temperature and pressure in determining whether sublimation occurs.
5. Recognize sublimation as an endothermic process and explain why it requires heat energy.
6. Discuss the potential environmental and industrial implications of sublimation processes.

By mastering these concepts, you'll have a solid understanding of sublimation and its significance in the world around us.