Where are the noble gases on the periodic table and what characteristics do they have?

the noble gases are those who occupy the eighth group of the periodic table and are so called because having the complete valence shell do not need to form bonds with other atoms and are thus in atomic form ...

The noble gases (also called rare gases) are of the inert gases that constitute the eighteenth [1] group of the periodic table of the elements, ie, the right-most column. They consist of atoms with electron shells full. It includes the following elements: helium neon argon krypton xenon radon Ununoctium Sometimes they (particularly helium) are located together with other gases (mostly nitrogen and methane) into endogenous sources; helium of endogenous origin comes from the decomposition of radioactive elements present in the subsurface that emit α particles (ie ions He2 +): These oxidized species present in the soil and become elio.I atoms of the noble gases are all monatomic gas, not easily liquefiable, present the atmosphere in different percentages; the most common is argon which is approximately the 0.932%.

The noble gases on the periodic table are a classification of gases that under standard conditions are all odorless, colorless, monatomic gases with very low chemical reactivity. There are six noble gases and they are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn). 

Adozen is 1221/12 = 1.751.75 x 12 = 21therefore, 1.75 is the answer.