Promethium (Pm). Diagram of the nuclear composition,electron configuration,chemical data,and valence orbitals of an atom of promethium-145 (atomic number: 61),an isotope of this element. The nucleus consists of 61 protons (red) and 84 neutrons (orange). 61 electrons (white) successively occupy available electron shells (rings). Promethium is a lanthanide in period 6,and the f-block of the periodic table. It melts at 1042 degrees Celsius. The trend across the lanthanide series arises from the failure of electrons filling an inner f-subshell (here,within the 4th ring) to shield outer (valence) electrons from increasing nuclear charge | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Clarivan, Carlos |
Bildgröße: | 5197 px × 5008 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |