Promethium

61
Pm
Skupina
n/a
Perioda
6
Blok
f
Protony
Elektrony
Neutrony
61
61
84
Hlavní vlastnosti
Atomové číslo
61
Atomová hmotnost
[145]
Hmotnostní číslo
145
Kategorie
Lanthanoidy
Barva
Stříbrná
Radioaktivní
Ano
Named after the Greek Prometheus, who, according to mythology, stole fire from heaven
Krystalografická soustava
n/a
Historie
The existence of an element between neodymium and samarium was first predicted by Czech chemist Bohuslav Brauner in 1902.

Promethium was first produced and characterized at Oak Ridge National Laboratory in 1945 by Jacob A. Marinsky, Lawrence E. Glendenin and Charles D. Coryell.

It was produced by the separation and analysis of the fission products of uranium fuel irradiated in a graphite reactor.
Elektronů v obalu
2, 8, 18, 23, 8, 2
Elektronová konfigurace
[Xe] 4f5 6s2
Pm
Promethium is the only lanthanide that has no stable isotopes
Fyzické vlastnosti
Skupenství
Pevná
Hustota
7,26 g/cm3
Teplota tání
1315,15 K | 1042 °C | 1907,6 °F
Teplota varu
3273,15 K | 3000 °C | 5432 °F
Skupenské teplo tání
7,7 kJ/mol
Skupenské teplo varu
290 kJ/mol
Měrná tepelná kapacita
-
Hojnost v zemské kůře
n/a
Hojnost ve vesmíru
n/a
Pitchblende,
Autorská práva obrázku: Wikimedia Commons (Geomartin)
Pitchblende, a uranium ore and the host for most of Earth's promethium
Číslo CAS
7440-12-2
PubChem CID číslo
n/a
Atomové vlastnosti
Atomový poloměr
183 pm
Kovalentní poloměr
199 pm
Elektronegativita
-
Ionizační potenciál
5,582 eV
Molární objem
22,39 cm3/mol
Tepelná vodivost
0,179 W/cm·K
Oxidační čísla
3
Aplikace
Promethium is also used in atomic batteries for spacecraft and guided missiles.

Promethium is also used to measure the thickness of materials by evaluating the amount of radiation from a promethium source that passes through the sample.

It has possible future uses in portable X-ray sources, and as auxiliary heat or power sources for space probes and satellites.
Promethium je škodlivé díky své radioaktivitě
Izotopy
Stabilní izotopy
-
Nestabilní izotopy
126Pm, 127Pm, 128Pm, 129Pm, 130Pm, 131Pm, 132Pm, 133Pm, 134Pm, 135Pm, 136Pm, 137Pm, 138Pm, 139Pm, 140Pm, 141Pm, 142Pm, 143Pm, 144Pm, 145Pm, 146Pm, 147Pm, 148Pm, 149Pm, 150Pm, 151Pm, 152Pm, 153Pm, 154Pm, 155Pm, 156Pm, 157Pm, 158Pm, 159Pm, 160Pm, 161Pm, 162Pm, 163Pm