The mineralogy of Berkelium

About Berkelium
Berkelium is a radioactive transuranic element that has only been produced in nuclear reactors. It is possible that some berkelium and other transuranic elements were created in the natural nuclear reactor in Oklo, Gabon.

General Properties
Symbol:	Bk
Atomic Number:	97
Standard atomic weight (A_r):	[247]
Electron configuration:	[Rn] 5f⁹ 7s²

Photos

<	13 milligrams of berkelium 249	>

Atomic Properties
Electronegativity (Pauling scale):	1.3
Atomic Radius:	170 pm
Ionic Radius:	96 pm (+3)
1st Ionization energy:	601 kJ/mol
Oxidation States:	3,4

Physical Properties
Standard State:	solid
Bonding Type:	metallic
Melting Point:	1323 K
Density:	14.78 g/cm³
Metal/Non-Metal:	actinoid

Main isotopes of Berkelium
Isotope	% in Nature	Half Life	Decay type	Decay product
²⁴⁵Bk	synthetic	4.94d	ε	²⁴⁵Cm
²⁴⁵Bk	synthetic	4.94d	α	²⁴¹Am
²⁴⁶Bk	synthetic	1.8d	α	²⁴²Am
²⁴⁶Bk	synthetic	1.8d	ε	²⁴⁶Cm
²⁴⁷Bk	synthetic	1380y	α	²⁴³Am
²⁴⁸Bk	synthetic	>300y	α	²⁴⁴Am
²⁴⁹Bk	synthetic	330d	α	²⁴⁵Am
			Spontaneous fission
			β−	²⁴⁹Cf

Other Information
Year Discovered:	1949
Discovered By:	Lawrence Berkeley National Laboratory
Named For:	after Berkeley, California, where it was discovered
CPK color coding:	#8A4FE3
External Links:	Wikipedia WebElements Los Alamos National Laboratory Theodore Gray's PeriodicTable.com

Simple Compounds
Fluorides	berkelium trifluoride	BkF₃	+3
Fluorides	berkelium tetrafluoride	BkF₄	+4
Chlorides	berkelium trichloride	BkCl₃	+3
Iodides	berkelium triiodide	BkI₃	+3
Oxides	berkelium oxide	BkO	+2
	berkelium dioxide	BkO₂	+4
	diberkelium trioxide	Bk₂O₃	+3

Periodic Table

2He

3Li

4Be

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Default Categories CPK Electronegativity Atomic Radius Lowest Oxidation Highest Oxidation Crustal Abundance Goldschmidt Mineral Species

Curium << Berkelium >> Californium

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Constants and physical property data from:

Lide, David R. - Ed. (2005) CRC Handbook of Chemistry and Physics - A Ready-Reference Book of Chemical and Physical Data (85th ed.). CRC Press.
National Physical Laboratory (2005) Kaye and Laby Online (discontinued). https://web.archive.org/web/20190506031327/http://www.kayelaby.npl.co.uk/
Kaye, G. W. C.; Laby, T. H. (n.d.) Tables of Physical and Chemical Constants and some Mathematical Functions. Longmans, Green, and Co.
Greenwood, N.N.; Earnshaw, A. (1997) Chemistry of the Elements (2nd ed.). Butterworth–Heinemann.
Ahrens, Thomas J. - Ed. (1995) Global Earth Physics - A Handbook of Physical Constants - AGU Reference Shelf No. 1. American Geophysical Union.
Railsback, L. Bruce (2003) An earth scientist's periodic table of the elements and their ions. Geology, 31 (9) 737 doi:10.1130/g19542.1
Emsley, John (2001) Nature's Building Blocks - An A-Z Guide to the Elements. Oxford University Press, Oxford.

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