1. Nitrogen (N2) - 78%
* Primary function: Nitrogen is relatively inert and acts as a diluent for the other gases in the atmosphere. It helps to regulate the temperature of the Earth and prevents extreme fluctuations.
* Other roles:
* Used by plants to produce proteins and nucleic acids (DNA and RNA).
* Used in industrial processes for the production of fertilizers, explosives, and other chemicals.
2. Oxygen (O2) - 21%
* Primary function: Essential for respiration in animals and plants. It's the key component in cellular energy production.
* Other roles:
* Supports combustion.
* Used in medical applications to treat respiratory problems.
3. Argon (Ar) - 0.93%
* Primary function: Inert gas, largely unreactive. Used to create an inert atmosphere in industrial processes.
* Other roles:
* Used in welding and lighting.
* Used in research and medical applications.
4. Carbon Dioxide (CO2) - 0.04%
* Primary function: A greenhouse gas that traps heat in the atmosphere. Important for the process of photosynthesis in plants.
* Other roles:
* Used in carbonated beverages.
* Used in the production of dry ice.
5. Trace Gases:
* Neon (Ne), Helium (He), Krypton (Kr), Xenon (Xe) - Inert gases, used in lighting, research, and medical applications.
* Water Vapor (H2O) - Varies depending on location and weather. Important for weather patterns, cloud formation, and the water cycle.
* Ozone (O3) - Absorbs harmful ultraviolet (UV) radiation from the sun in the stratosphere.
* Methane (CH4) - A powerful greenhouse gas, released from natural sources and human activities.
* Other gases: Include pollutants like nitrogen oxides (NOx), sulfur dioxide (SO2), and particulate matter, which have negative impacts on human health and the environment.
Important Note: The exact composition of air can vary depending on location, altitude, and other factors. However, the proportions listed above are generally representative of the Earth's atmosphere.
