n
1.008665
0
neutron
n
1.008665
0
neutron
H
1.00797
1
hydrogen
H
1.00797
1
hydrogen
He
4.0026
2
helium
He
4.0026
2
helium
Li
6.941
3
lithium
Be
9.01218
4
beryllium
B
10.811
5
boron
C
12.011
6
carbon
N
14.0067
7
nitrogen
O
15.9994
8
oxygen
F
18.9984
9
fluorine
Ne
20.1797
10
neon
Ne
20.1797
10
neon
Na
22.98977
11
sodium
Mg
24.305
12
magnesium
Al
26.98154
13
aluminum
Si
28.0855
14
silicon
P
30.97376
15
phosphorus
S
32.066
16
sulfur
Cl
35.4527
17
chlorine
Ar
39.948
18
argon
Ar
39.948
18
argon
K
39.0983
19
potassium
Ca
40.078
20
calcium
Ge
72.61
32
germanium
As
74.9216
33
arsenic
Se
78.96
34
selenium
Br
79.904
35
bromine
Kr
83.8
36
krypton
Kr
83.8
36
krypton
Rb
85.4678
37
rubidium
Sr
87.62
38
strontium
Sn
118.71
50
tin
Sb
121.757
51
antimony
Te
127.6
52
tellurium
I
126.9045
53
iodine
Xe
131.29
54
xenon
Xe
131.29
54
xenon
Cs
132.9054
55
cesium
Ba
137.33
56
barium
Pb
207.2
82
lead
Bi
208.9804
83
bismuth
Po
209
84
polonium
At
210
85
astatine
Rn
222
86
radon
Rn
222
86
radon
Fr
223
87
francium
Ra
226.0254
88
radium
Fl
289
114
flerovium
Mc
288
115
moscovium
Lv
293
116
livermorium
Ts
294
117
tennessine
Og
294
118
oganesson
Og
294
118
oganesson