Level + period | Group | I | II | III | IV | V | VI | VII |
2A | 3 Li | 4Be | 5B | 6C | 7N | 8O | 9F | |
3A | 11Na | 12Mg | 13Al | 14 Si | 15P | 16S | 17Cl | |
4A | 19K | 20Ca | 21Sc | 22 Ti | 23V | 24Cr | 25Mn | |
5A | 37Rb | 38Sr | 39Y | 40Zr | 41Nb | 42Mo | 43Tc | |
6A | 55Cs | 56Ba | 57La 71Lu | 72Hf | 73Ta | 74W | 75Re | |
7A | 87Fr | 88Ra | 89Ac 103Lr | 104Rf | 105Db | 106Sg | 107Bh |