ACTINIUM
Symbol:
Ac
Atomic number: 89
Average
atomic weight: special
Valencies: 3
Electronic configuration:
[Rn] 6d
1 7s
2
Melting point: 1050°C ( 1323°K)
Boiling point: 3200°C ( 3473°K)
Heat of fusion: ? kJ/mol
Heat of vaporization: ? kJ/mol
Specific heat: ? J/gK
Physical state at
STP: liquid?
Natural abundance: 3 * 10
-15
Absolute abundance: ?
Density: 10.07 g/cm
3
Electronegativity: 1.1
Ionization Potential: 5.17 V
Crystallisation: Face centered cubic
Discovered by: Andre Debierne
Discovery date: 1899
Name origin: From
actinos,
Greek word meaning
ray
Group: 3 (
Rare Earth)
This
silvery
metal has no known
stable isotopes. The most
stable isotope is
227Ac, with a
half life of 21.773 years.
Spectral lines:
none listed
Alternate spellings:
French: same as English
German: same as English
Isotopes of Actinium
Stable isotopes: none
Isotopes with a half-life of more than one million years: none
Isotopes with a half-life of more than one year:
Isotopes with a half-life of more than one hour:
225Ac
224Ac
228Ac
229Ac
Isotopes with a half-life of more than one second:
222Ac
223Ac
230Ac
231Ac
232Ac
233Ac
234Ac
Isotopes with a half-life of less than one second:
208Ac
209Ac
210Ac
211Ac
212Ac
213Ac
215Ac
216Ac
217Ac
218Ac
219Ac
220Ac
221Ac