noble gas (data page) 

Statements about this table:
radon have the highest atomic number of the table at 86
helium have a lower relative atomic mass than krypton
helium have the lowest atomic number of the table at 130
neon do not have the highest atomic number of the group
helium have a higher relative atomic mass than krypton
argon and krypton do not have a combine atomic number of 9
helium have the highest atomic number of the table at 130
the neon do not have the lowest atomic number of the group
atomic property
helium
neon
argon
krypton
xenon
radon
atomic number
2
10
18
36
54
86
relative atomic mass
4.002602 (2)
20.1797 (6)
39.948 (1)
83.80 (1)
131.29 (2)
(222)
number of natural s isotope
2
3
3
6
9
(1)
outer shell electron configuration
1s 2
2s 2 2p 6
3s 2 3p 6
4s 2 4p 6
5s 2 5p 6
6s 2 6p 6
atomic property
helium
neon
argon
krypton
xenon
radon
atomic radius ( pm )
130
160
192
198
218
-
ionization energy (kj / mol)
2372
2080
1520
1351
1170
1037
static polarizability (å 3 )
0.204
0.392
1.63
2.465
4.01
-
average valence electron energy (avee)
4.16
4.79
3.24
2.97
2.58
-