Chapter 11 Introduction
The hot air inside a balloon has extremely low density and it causes the balloon to rise. Density differences cause warm air masses to rise in the atmosphere in a similar way.
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CHAPTER 11
Pressing Matter
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In this chapter, you will study
the density of gases
the behavior of gas particles
the relationships between gas pressure, temperature, and volume
high- and low-pressure weather systems
The atoms and molecules in solids, liquids, and gases are always in motion. However, gas molecules are free to move to fill the entire space of their container. Gas molecules collide with one another and with anything else they come in contact with, causing pressure. When samples of gases are placed in containers, it is possible to measure the relationships between gas pressure, temperature, and volume. The air pressure of the atmosphere has a great deal of influence on the weather.