Periodic Table of Elements

02/05/09

Tm

Thulium

Atomic Number

69

Atomic Symbol

Tm

Name

Thulium

	Meaning	Named for Thule, early name for Scandinavia
	Group	Rare earth

Atomic Weight

168.93421

Density, g/cubic cm at STP

9.321

Melting Point, °C

1545

Boiling Point, °C, 1 atm

1947

Naturally Occurring Isotopes

Tm-169

Discoverer

Cleve

Year

1879

Ionization Energy, eV

6.1843

Configuration

[Xe] 4f13 6s2

Description

Silvery-white

Information Thulium is a rare earth metal that is in fact very rare, and has almost no applications (although there are reports of thulium being used for eye-safe lasers). Joseph's Element Collection Joseph has not yet obtained a sample of Thulium. References: Holden, Norman E. (March 30, 2004). "History of the origin of the chemical elements and their discoverers." National Nuclear Data Center. Retrieved October 7, 2005 from http://www.nndc.bnl.gov/content/elements.html "List of elements by boiling point." (September 22, 2005). Wikipedia. Retrieved October 9, 2005 from http://en.wikipedia.org/wiki/List_of_elements_by_boiling_point "List of elements by density." (September 22, 2005). Wikipedia. Retrieved October 9, 2005 from http://en.wikipedia.org/wiki/List_of_elements_by_density "List of elements by melting point." (September 22, 2005). Wikipedia. Retrieved October 9, 2005 from http://en.wikipedia.org/wiki/List_of_elements_by_melting_point "NIST chemistry webBook." (2005). National Institute of Standards and Technology. Retrieved October 6, 2005 from http://webbook.nist.gov/chemistry/ Zucker, M.A.; Kishore, A. R.; Sukumar, R.; and Dragoset, R. A. (July 2005). "Elemental data index."  National Institute of Standards and Technology. Retrieved October 7, 2005 from http://physics.nist.gov/PhysRefData/Elements/cover.html