Is Air a Compound or a Mixture?

Thomas G./Pexels

Air is a mixture of a variety of gases and components that are evenly distributed. Air is not a compound.

Difference Between Mixture and Compound

Knowing the difference between a mixture and a compound helps to understand the makeup of air. Mixtures are created by two or more mixed substances. Mixtures can also be either homogeneous or heterogeneous. Once combined, the components of the mixture can also be separated. 

Compounds are created from two or more chemically mixed elements. It is a new substance formed by the components’ reaction with the other. This pure form is often homogeneous in nature. 

What Is in the Air?

According to the National Aeronautics and Space Administration, the composition of the elements in our atmosphere is made up mostly of nitrogen (78%) and oxygen (21%). The remaining 1% is a minute mix of helium, hydrogen, carbon dioxide, and others. 

Impact on Air

Land and water both have a measurable impact on air. Each of these surfaces can absorb heat and produce heat to give off. But a land surface radiates its heat quickly from the day into our air at night while the heat from a water surface, by comparison, takes a longer time to move into the air. 

Air and Land

A land surface heats up quickly in the daytime but loses its heat during the night. As the air temperature drops during the night, so too does the land surface temperature. You see this frequently in United States desert cities like Phoenix, Arizona, and Las Vegas, Nevada. Hot air during the day causes the land surface to rise in dangerous temperatures. 

Air and Water

Masses of water, like oceans and large lakes, absorb heat more slowly during the day and can retain much of its gained heat through the night. This is why the ocean will often seem warmer during the night. An example that shows this is if you walk on a hot beach during the day, the sand will be very hot to your feet, yet the water will be cool. At nighttime, the sand is much cooler, but the water in the ocean is relatively warm.

Air Pollutants

Nitrogen and oxygen are the main gases in air. However, air also contains many tiny particles like pollen and dust. These are known as aerosols and are swept up in the air from the wind. Other particles like smoke, exhaust, and machine debris can contribute to air pollution.

How Ozone Affects Air

The mixture of pollutants and gases in our air can cause ozone to form. Ozone is a gas that can be found at Earth’s ground level as well as in the upper atmosphere. This ozone high in the air helps protect our planet from the ultraviolet rays of the sun. However, in recent decades, man-made chemicals have caused more damage to this protective layer and caused holes in the ozone layer. Additionally, when cars, chemical plants, or machine refineries emit pollutants, this can cause ground-level ozone, which is harmful to the air people breathe.