Ozone

Ozone is a colorless gas composed of three bonded oxygen atoms (O₃), found naturally in Earth's atmosphere and produced artificially for various industrial purposes. Its name derives from the Greek ozein, meaning "to smell"—a reference to its distinctive pungent odor, often noticed after lightning strikes or near electrical equipment.

In the upper atmosphere, ozone forms a protective layer that absorbs harmful ultraviolet radiation from the sun, shielding life on Earth. This "ozone layer" has become a focus of environmental concern due to depletion caused by chlorofluorocarbons (CFCs) and other chemicals.

Closer to Earth's surface, ground-level ozone is a secondary air pollutant created when nitrogen oxides and volatile organic compounds react in sunlight. Unlike stratospheric ozone, tropospheric ozone damages respiratory health and plant life.

Industrially, ozone is valued as a powerful oxidizing agent used in water purification, bleaching, and sterilization. Its reactive nature makes it effective but also unstable—it decomposes quickly back into ordinary oxygen.

The discovery and study of ozone catalyzed modern chemistry and atmospheric science, revealing how chemical reactions shape planetary systems.

Related

Stratosphere, Ultraviolet radiation, Oxidation, Photochemistry, Environmental protection