Số proton
Element Name
Chemical symbols
Relative atomic mass
Valence
1 Hydrogen H 1 I
2 Helium He 4
3 Lithium Li 7 I
4 Beryllium Be 9 II
5 Boron B 11 III
6 Carbon C 12 IV, II
7 Nitrogen N 14 II, III, IV…
8 Oxygen O 16 II
9 Flourine F 19 I
10 Neon Ne 20
11 Sodium Na 23 I
12 Magnesium Mg 24 II
13 Aluminum Al 27 III
14 Silicon Si 28 IV
15 Phosphorus P 31 III, V
16 Sulfur S 32 II, IV, VI
17 Chloride Cl 35,5 I,…
18 Argon Ar 39,9
19 Potassium K 39 I
20 Calcium Ca 40 II
24 Chromium Cr 52 II, III
25 Manganese Mn 55 II, IV, VII…
26 Iron Fe 56 II, III
29 Copper Cu 64 I, II
30 Zinc Zn 65 II
35 Bromine Br 80 I…
47 Silver Ag 108 I
56 Barium Ba 137 II
80 Mercury Hg 201 I, II
82 Lead Pb 207 II, IV
