Inert gas Inert gas An inert gas/noble gas is a gas which does not undergo chemical reactions under a set of given conditions. The noble gases often do not react with many substances, and were historically referred to as the inert gases. Inert gases are used generally to avoid unwanted chemical reactions degrading a sample. These undesirable chemical reactions are often oxidation and hydrolysis reactions with the oxygen and moisture in air. The term "inert gas" is context-dependent because several of the noble gases can be made to react under certain conditions. Purified argon and nitrogen gases are most commonly used as
Incandescent light bulb sources are radiant efficiencies and efficacies. A similar chart in the article on luminous efficacy compares a broader array of light sources to one another. The spectrum emitted by a blackbody radiator at temperatures of incandescent bulbs does not match the sensitivity characteristics of the human eye. Most of the radiation is not in the range of wavelengths to which the eye is sensitive. Tungsten filaments radiate mostly infrared radiation at temperatures where they remain solid – below . Donald L. Klipstein explains it this way: "An ideal thermal radiator produces visible light most efficiently at temperatures around . Even