Oksigenit

Oksigenit is a term that may be encountered in non-English sources to refer to oxygen or to oxygen-containing substances. In English-language chemistry the standard term is oxygen, and oksigenit is not widely used as a formal designation. In some contexts it can indicate the plural of a word for oxygen in certain languages or be used informally to describe oxygen-bearing materials.

Oxygen is a chemical element with the symbol O and atomic number 8. It primarily exists as a diatomic molecule (O2) in Earth's atmosphere and is essential for aerobic respiration and many combustion processes. It makes up about 21% of the atmosphere and is the third most abundant element in the universe by mass. Oxygen is highly reactive, forming oxides with nearly all elements. In the upper atmosphere, ozone (O3) forms and helps shield the planet from ultraviolet radiation.

Industrial production of oxygen is chiefly by fractional distillation of liquid air or by methods such as pressure swing adsorption and electrolysis. Oxygen participates in a wide range of chemical reactions and compounds, including water (H2O), carbon dioxide (CO2), and numerous metal oxides such as iron(III) oxide (Fe2O3). The common oxidation state of oxygen in compounds is −2.

Natural isotopes of oxygen include 16O, 17O, and 18O, with abundances about 99.76%, 0.04%, and 0.20% respectively. Oxygen was independently isolated in 1774–1775 by Joseph Priestley and Carl Wilhelm Scheele; the element’s name was popularized by Antoine Lavoisier.

Safety and usage notes: oxygen is non-toxic at normal atmospheric concentrations but supports combustion, and enriched or high-pressure environments can pose fire and health risks. See also the oxygen cycle, oxides, and ozone.