Ædelgasserne

Ædelgasserne, also known as noble gases, are a group of chemical elements that make up Group 18 of the periodic table. These elements include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). They are characterized by their very low chemical reactivity, due to having a full valence electron shell. This makes them monatomic gases under standard conditions.

Historically, these elements were considered completely inert, hence the name "noble." However, research has shown that some of the heavier noble gases, particularly xenon and krypton, can form compounds under specific conditions with highly electronegative elements like fluorine and oxygen. Radon, being radioactive, is also a notable member of this group, posing health risks due to its radioactivity.

Ædelgasserne have a variety of important applications. Helium is used in balloons, airships, and as a cooling agent for superconducting magnets. Neon is famously used in neon signs, producing a bright reddish-orange light. Argon is widely employed as a protective atmosphere in welding and in incandescent light bulbs to prevent filament oxidation. Krypton and xenon find uses in high-intensity lighting, such as in photographic flashes and some types of lamps, and xenon is also used in some anesthetic procedures. Despite their name, a deeper understanding of their chemistry has revealed their utility and some limited reactivity.