Here's a breakdown:
* Air composition: Air is primarily composed of nitrogen (N2) and oxygen (O2), with smaller amounts of other gases like argon (Ar), carbon dioxide (CO2), and trace amounts of other elements and compounds.
* Particle nature: These gases exist as molecules, which are the smallest units of a substance that retain the chemical properties of that substance.
* Movement: Whether air is moving fast or slow, the molecules within it are constantly in motion. They collide with each other and with surfaces.
* Speed and density: In fast-moving air, the average speed of the molecules is higher than in slow-moving air. However, the density of the air remains relatively constant, meaning the number of molecules per unit volume stays the same.
Key point: The speed of the air refers to the collective motion of the gas molecules. The individual molecules are always in motion, even in still air.
