2.  Noble gases make up a group of chemical elements with similar properties  The properties include being odorless, colorless, low chemical reactivity, and are monatomic gases.  Their outer shell of valence electrons is considered to be “full”, which gives them little tendency to participate in chemical reactions  Weak interatomic force  Low melting and boiling points

3.  The six noble gases that occur naturally are Helium, Neon, Argon, Krypton, Xenon, and Radon. ElementNumber of electrons Helium2 Neon10 Argon18 Krypton36 Xenon54 Radon86

4.  Noble gases do not form ions because they already have the perfect number of electrons in their topmost energy levels  Incapable of reacting with other elements under room temperature