The key difference between air and oxygen lies in their composition; oxygen is a single element, while air is a mixture of many gases.
Composition Differences
Here's a detailed breakdown:
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Oxygen (O2): Consists solely of oxygen molecules. It is a colorless, odorless, and tasteless gas crucial for respiration in most living organisms and combustion processes.
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Air: A complex mixture containing multiple elements and compounds. The major components of dry air are:
Gas Percentage (by Volume) Nitrogen (N2) ~78% Oxygen (O2) ~21% Argon (Ar) ~0.9% Carbon Dioxide (CO2) ~0.04% Other gases (Ne, He, CH4, Kr, H2, Xe, etc.) Trace amounts Additionally, air can contain variable amounts of water vapor, dust, pollen, and other airborne particles.
Key distinctions summarised:
- Purity: Oxygen is a pure substance containing only oxygen, while air is a complex mixture of gases.
- Primary components: Oxygen is the only component in oxygen gas, while air contains primarily nitrogen and oxygen with trace amounts of other gases.
- Use: While both are necessary for life, oxygen is used in specific industrial and medical applications due to its high concentration, whereas air is the mixture we breathe.
- Other elements: Air contains many trace elements such as methane, krypton and iodine according to the provided reference, these elements are absent from pure oxygen.
Practical Implications
- Medical: Oxygen tanks in hospitals contain concentrated oxygen, not just air, to assist patients with breathing difficulties.
- Industry: Oxygen is used in welding and other processes needing intense combustion. Air is often used for pneumatic tools and other general-purpose applications.
In essence, the difference is that air contains oxygen as a key component, alongside several other gases, while oxygen is a pure gas by itself.
