home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
CD School House 9
/
CD School House 9.0 - Wayzata Technology (1994).iso
/
pc
/
dos
/
math
/
teeote
/
promethi.asc
< prev
next >
Wrap
Text File
|
1992-08-23
|
625b
|
17 lines
PROMETHIUM
Atomic symbol - Pm
Atomic weight - (144.9127)
Atomic number - 61
Electron configuration - 2-8-18-23-8-2
Oxidation states - +3
State of matter - synthetic
Heavy metal-brittle
Discovered in 1947 by J.A. Marinsky, L.E. Glendenin, and C.D. Coryell
Boils at 2460 °C, melts at 1080 °C
Notes:
Promethium was the last of the rare-earth metals to be discovered. Its soft
beta radiation can be coverted into electricity by sandwiching promethium and
semiconductors such as silicon together; these "batteries" can last as long as
5 years in extreme temperatures.