Electron Configuration Chart

Electron Configurations of Atoms of Elements

Orbital representation diagram depicting each orbital of an atom having its own circle within each sublevel
Adrignola/Wikimedia Commons/CC 3.0

The electron configuration of an atom of any element is the of electrons per sublevel of the energy levels of an atom in its ground state. This handy chart compiles the electron configurations of the elements up through number 104.

How to Determine Electron Configuration

To arrive at the electron configurations of atoms, you must know the order in which the different sublevels are filled. Electrons enter available sublevels in order of their increasing energy. A sublevel is filled or half-filled before the next sublevel is entered.

For example, the s sublevel can only hold two electrons, so the 1s is filled at helium (1s2). The p sublevel can hold six electrons, the d sublevel can hold 10 electrons, and the f sublevel can hold 14 electrons. The common shorthand notation is to refer to the noble gas core, rather than write out the entire configuration. For example, the configuration of magnesium could be written [Ne]3s2, rather than writing out 1s22s22p63s2.

Electron Configuration Chart

No. Element K L M N O P Q
1 2 3 4 5 6 7
s s p s p d s p d f s p d f s p d f s
1 H 1
2 He 2
3 Li 2 1
4 Be 2 2
5 B 2 2 1
6 C 2 2 2
7 N 2 2 3
8 O 2 2 4
9 F 2 2 5
10 Ne 2 2 6
11 Na 2 2 6 1
12 Mg 2 2 6 2
13 Al 2 2 6 2 1
14 Si 2 2 6 2 2
15 P 2 2 6 2 3
16 S 2 2 6 2 4
17 Cl 2 2 6 2 5
18 Ar 2 2 6 2 6
19 K 2 2 6 2 6 - 1
20 Ca 2 2 6 2 6 - 2
21 Sc 2 2 6 2 6 1 2
22 Ti 2 2 6 2 6 2 2
23 V 2 2 6 2 6 3 2
24 Cr 2 2 6 2 6 5* 1
25 Mn 2 2 6 2 6 5 2
26 Fe 2 2 6 2 6 6 2
27 Co 2 2 6 2 6 7 2
28 Ni 2 2 6 2 6 8 2
29 Cu 2 2 6 2 6 10 1*
30 Zn 2 2 6 2 6 10 2
31 Ga 2 2 6 2 6 10 2 1
32 Ge 2 2 6 2 6 10 2 2
33 As 2 2 6 2 6 10 2 3
34 Se 2 2 6 2 6 10 2 4
35 Br 2 2 6 2 6 10 2 5
36 Kr 2 2 6 2 6 10 2 6
37 Rb 2 2 6 2 6 10 2 6 - 1
38 Sr 2 2 6 2 6 10 2 6 - 2
39 Y 2 2 6 2 6 10 2 6 1 2
40 Zr 2 2 6 2 6 10 2 6 2 2
41 Nb 2 2 6 2 6 10 2 6 4* 1
42 Mo 2 2 6 2 6 10 2 6 5 1
43 Tc 2 2 6 2 6 10 2 6 6 1
44 Ru 2 2 6 2 6 10 2 6 7 1
45 Rh 2 2 6 2 6 10 2 6 8 1
46 Pd 2 2 6 2 6 10 2 6 10 0*
47 Ag 2 2 6 2 6 10 2 6 10 1
48 Cd 2 2 6 2 6 10 2 6 10 2
49 In 2 2 6 2 6 10 2 6 10 2 1
50 Sn 2 2 6 2 6 10 2 6 10 2 2
51 Sb 2 2 6 2 6 10 2 6 10 2 3
52 Te 2 2 6 2 6 10 2 6 10 2 4
53 I 2 2 6 2 6 10 2 6 10 2 5
54 Xe 2 2 6 2 6 10 2 6 10 2 6
55 Cs 2 2 6 2 6 10 2 6 10 2 6 - - 1
56 Ba 2 2 6 2 6 10 2 6 10 2 6 - - 2
57 La 2 2 6 2 6 10 2 6 10 - 2 6 1 - 2
58 Ce 2 2 6 2 6 10 2 6 10 2* 2 6 - - 2
59 Pr 2 2 6 2 6 10 2 6 10 3 2 6 - - 2
60 Nd 2 2 6 2 6 10 2 6 10 4 2 6 - - 2
61 Pm 2 2 6 2 6 10 2 6 10 5 2 6 - - 2
62 Sm 2 2 6 2 6 10 2 6 10 6 2 6 - - 2
63 Eu 2 2 6 2 6 10 2 6 10 7 2 6 - - 2
64 Gd 2 2 6 2 6 10 2 6 10 7 2 6 1 - 2
65 Tb 2 2 6 2 6 10 2 6 10 9* 2 6 - - 2
66 Dy 2 2 6 2 6 10 2 6 10 10 2 6 - - 2
67 Ho 2 2 6 2 6 10 2 6 10 11 2 6 - - 2
68 Er 2 2 6 2 6 10 2 6 10 12 2 6 - - 2
69 Tm 2 2 6 2 6 10 2 6 10 13 2 6 - - 2
70 Yb 2 2 6 2 6 10 2 6 10 14 2 6 - - 2
71 Lu 2 2 6 2 6 10 2 6 10 14 2 6 1 - 2
72 Hf 2 2 6 2 6 10 2 6 10 14 2 6 2 - 2
73 Ta 2 2 6 2 6 10 2 6 10 14 2 6 3 - 2
74 W 2 2 6 2 6 10 2 6 10 14 2 6 4 - 2
75 Re 2 2 6 2 6 10 2 6 10 14 2 6 5 - 2
76 Os 2 2 6 2 6 10 2 6 10 14 2 6 6 - 2
77 Ir 2 2 6 2 6 10 2 6 10 14 2 6 7 - 2
78 Pt 2 2 6 2 6 10 2 6 10 14 2 6 9 - 1
79 Au 2 2 6 2 6 10 2 6 10 14 2 6 10 - 1
80 Hg 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2
81 Tl 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 1 - -
82 Pb 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 2 - -
83 Bi 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 3 - -
84 Po 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 4 - -
85 At 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 5 - -
86 Rn 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 6 - -
87 Fr 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 6 - - 1
88 Ra 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 6 - - 2
89 Ac 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 6 1 - 2
90 Th 2 2 6 2 6 10 2 6 10 14 2 6 10 - 2 6 2 - 2
91 Pa 2 2 6 2 6 10 2 6 10 14 2 6 10 2* 2 6 1 - 2
92 U 2 2 6 2 6 10 2 6 10 14 2 6 10 3 2 6 1 - 2
93 Np 2 2 6 2 6 10 2 6 10 14 2 6 10 4 2 6 1 - 2
94 Pu 2 2 6 2 6 10 2 6 10 14 2 6 10 6 2 6 - - 2
95 Am 2 2 6 2 6 10 2 6 10 14 2 6 10 7 2 6 - - 2
96 Cm 2 2 6 2 6 10 2 6 10 14 2 6 10 7 2 6 1 - 2
97 Bk 2 2 6 2 6 10 2 6 10 14 2 6 10 9* 2 6 - - 2
98 Cf 2 2 6 2 6 10 2 6 10 14 2 6 10 10 2 6 - - 2
99 Es 2 2 6 2 6 10 2 6 10 14 2 6 10 11 2 6 - - 2
100 Fm 2 2 6 2 6 10 2 6 10 14 2 6 10 12 2 6 - - 2
101 Md 2 2 6 2 6 10 2 6 10 14 2 6 10 13 2 6 - - 2
102 No 2 2 6 2 6 10 2 6 10 14 2 6 10 14 2 6 - - 2
103 Lr 2 2 6 2 6 10 2 6 10 14 2 6 10 14 2 6 1 - 2
104 Rf 2 2 6 2 6 10 2 6 10 14 2 6 10 14 2 6 2 - 2

* note the irregularity

You may also view the electron configurations of the elements on a printable periodic table if desired.