1 valence electron
+1
2 valence electrons
+2
Group 1
hydrogen 1.01 (H is a nonmetal)
2s
Li
3
Group 2
Na
3s
sodium
Mg 24.31
4s
K potassium
Ca
20
calcium 40.08
39.10
5s
ď Š
37
Rb
rubidium
38
55
132.91 87
7s
Cs
cesium
6s
Fr
francium 223.02
Sr
strontium 87.62
85.47 56
Ba
barium 137.33 88
Ra
radium
226.02
3p
Transition metals: 2 valence electrons
magnesium
22.99 19
B
2p
9.01 12
Group 3
Sc
21
3d
scandium 44.96 39
4d
Y
yttrium 88.91
Lu
71
5d
Group 4
22
titanium 47.90 40
Hf
72
hafnium 178.49
Lr
104
262.11
57
La
Ac
actinium 227.03
41
Ce cerium 140.12
90
Th
thorium 232.04
Nb
niobium 92.91 73
Ta
tantalum
Group 6
Cr
24
105
Db
dubnium 262.11
59
Pr
praseodymium
140.91 91
Pa
protactinium
231.04
Group 7
Mn
25
chromium manganese 52.00 54.94 42
Mo
43
W
75
molybdenum 95.94 74
Re
76
rhenium 186.21
Sg
seaborgium
107
263.12
60
Nd
neodymium 144.24 92
U uranium 238.03
Bh
bohrium 264.12
61
Pm
promethium 144.91 93
Np
neptunium 237.05
Fe
iron 55.85 44
183.85 106
Group 8
26
Tc
technetium 96.91
tungsten
180.95
261.11
58
lanthanum 138.91 89
Rf
rutherfordium
V
vanadium 50.94
91.22
174.97
6d lawrencium
5f
Zr
Group 5
23
zirconium
Lutetium
103
4f
Ti
Ru
Group 9
27
cobalt 58.93 45
ruthenium 101.07
Os
osmium 190.20
Hs
108
hassium
77
Sm
samarium 150.41 94
Pu
plutonium 244.06
Group 10
46
Ir
78
Pd
195.09
Mt
110
Ds
Eu
europium 151.96 95
Am
americium 243.06
silver 107.87 79
Au
gold 196.97 111
Rg
Darmstadtium roentgenium
(268)
63
Ag
47
Pt
platinum
Cu
copper 63.55
palladium 106.40
192.22
Meitnerium
29
nickel 58.71
iridium
109
Group 11
Ni
28
Rh
rhodium 102.91
265.13
62
Co
(272)
(281)
64
Gd
gadolinium 157.25 96
Cm
curium (247)
65
Tb
terbium 158.92 97
Bk
berkelium (249)
Al
13
Zn
zinc 65.37
Cd
48
cadmium 112.40 80
Hg
mercury 200.59 112
Uub
Ununbium (285)
66
Dy
dysprosium 162.50 98
Cf
californium (251)
4p
gallium
indium 114.82
7p 67
Pb
83
Uut
52
Bi
84
bismuth
Uuq
115
F
Te Po
Uup
116
Uuh
Ne neon
19.00
20.18
Cl
17
Ar
18
chlorine
argon
35.45
39.95
Br bromine
35
I
53
krypton 83.80
Xe
54
iodine 126.90
xenon 131.30 86
At
85
Kr
36
79.91
tellurium 127.60
polonium (210)
208.98
207.19 114
Sb
Antimony) 121.75
He helium 4.00
10
astatine
Rn
radon
(210)
(220)
Uus
117
118
Uuo
ununtrium ununquadium ununpentium ununhexium ununseptium ununoctium (289) (295) (284) (289) (288) (293)
Ho
Holmium 164.93 99
51
lead
204.37 113
Sn
82
thallium
selenium 78.96
74.92
tin 118.69
Tl
81
6p
50
In
49
5p
arsenic
72.59
Se
34
2
fluorine
32.07
As
33
germanium
69.72
sulfur
30.97
Ge
32
S
16
phosphorus
28.09
Ga
O
16.00
P
15
-1
Group 17
9
oxygen
14.01
silicon
26.98 31
N
8
Noble gases
Group 18
halogens
Group 16
nitrogen
Si
14
aluminum
Group 12
30
C
6
Group 15
7
carbon 12.01
7
-3 -2
Group 14
6
boron 10.81
5
+4, -4
+3
5
beryllium
6.94
4
Group 13
Be
4
lithium 11
metal
1s
3
0
8
Valence electrons:
Alkaline earth metals
H
1
nonmetal
Alkali metals
Es
einsteinium (254)
68
Er
erbium 167.26 100
Fm
fermium 257.10
Tm
69
thulium 168.93 101
Md
mendelevium (256)
Yb
70
ytterbium 173.04 102
No
nobelium (254)
Atomic number to 71
21
Symbol:
Sc
scandium to 103
44.96 metal metalloid
Solid Liquid Gas
Manmade
name Atomic mass nonmetal