Final answer:
Noble gases, also known as inert gases, are elements in group 18 of the periodic table. They are historically thought to be nonreactive but can actually react with fluorine to form compounds. They have low reactivity and are primarily used in inert atmospheres, neon signs, and as coolants.
Step-by-step explanation:
The noble gases, also known as inert gases, are elements in group 18 of the periodic table, which include helium, neon, argon, krypton, xenon, and radon. They earned the name 'noble' because they were historically thought to be nonreactive due to their filled valence shells. However, this assumption was proven false by Dr. Neil Bartlett in 1962.
Noble gases have low reactivity and occur in low concentrations in the atmosphere. They are primarily used as inert atmospheres, in neon signs, and as coolants. The heaviest noble gases can react with fluorine to form compounds.
The noble gases exist as monatomic gases, meaning they consist of single atoms, unlike other nonmetal gases such as hydrogen, nitrogen, oxygen, fluorine, and chlorine, which usually exist as diatomic molecules.
Learn more about Noble gases