Definitions for "Noble gases"
Keywords:  inert, helium, radon, krypton, xenon
The noble gases are the elements in Group 0/Group VIII of the periodic table. They have a full outer shell of electrons and so are unreactive. The periodic table
the chemically inert elements of the helium group of the periodic table. The noble gas family consists of six different elements, five of which have stable isotopes (helium, neon, argon, krypton, and xenon), and one that has only radioactive isotopes (radon).
The last column of the periodic table lists the inert or noble gases. In these gases, the outer shell of electrons in each atom is completely filled, making them very unreactive. Because of their unreactive nature, these gases are often called inert, even "noble" gases.