Mononuclidic element Complete list of the 22 mononuclidic elements Complete list of the 22 mononuclidic elements

| Element_ | Nuclide | Z_p_ | N_n_ | isotopic_mass_u_ |
|---|---|---|---|---|
| beryllium | 9 Be | 4 | 5 | 9.012 182(3) |
| fluorine | 19 F | 9 | 10 | 18.998 403 2(5) |
| sodium | 23 Na | 11 | 12 | 22.989 770(2) |
| aluminium | 27 Al | 13 | 14 | 26.981 538(2) |
| phosphorus | 31 P | 15 | 16 | 30.973 761(2) |
| scandium | 45 Sc | 21 | 24 | 44.955 910(8) |
| manganese | 55 Mn | 25 | 30 | 54.938 049(9) |
| cobalt | 59 Co | 27 | 32 | 58.933 200(9) |
| arsenic | 75 As | 33 | 42 | 74.921 60(2) |
| yttrium | 89 Y | 39 | 50 | 88.905 85(2) |
| niobium | 93 Nb | 41 | 52 | 92.906 38(2) |
| rhodium | 103 Rh | 45 | 58 | 102.905 50(2) |
| iodine | 127 I | 53 | 74 | 126.904 47(3) |
| caesium | 133 Cs | 55 | 78 | 132.905 45(2) |