thulium

Home > ... > Science and Technology > Chemistry > Compounds and Elements > ...

Essential
reading

Compare
side-by-side

The Oxford Pocket Dictionary ...

World Encyclopedia

The Columbia Encyclopedia, ...

thulium

The Columbia Encyclopedia, Sixth Edition | 2008 | The Columbia Encyclopedia, Sixth Edition. Copyright 2008 Columbia University Press. (Hide copyright information) Copyright

thulium [from Thule, an ancient name for Scandinavia], metallic chemical element; symbol Tm; at. no. 69; at. wt. 168.9342; m.p. about 1,545°C; b.p. 1,947°C; sp. gr. 9.3; valence +3. Thulium is a soft, malleable, ductile, lustrous silver-white metal. It is one of the rare-earth metals of the lanthanide series in Group 3 of the periodic table . It does not tarnish rapidly in dry air but should be protected from moisture. It forms compounds with oxygen and the halogens, most of which are light green. The oxide, Tm 2 O 3 , is called thulia. Thulium is the least abundant of the rare-earth metals. It is found in the minerals gadolinite and euxenite and in monazite, the chief commercial source. The metal can be obtained by chemical reduction of its compounds. The pure metal and compounds have few commercial uses, but they are often used without purification in combination with the other rare-earth metals and compounds, e.g., in lighter flints and carbon electrodes for arc lighting. Although the only naturally occurring isotope (thulium-169) is stable, there are 15 unstable isotopes. Thulium-170 (half-life about 129 days), prepared by irradiating thulium-169 in a nuclear reactor, emits X rays; it is used in portable X-ray sources. Thulium was discovered in 1879 by P. T. Cleve.

Hide all research tools
Print this article Print all entries for this topic Cite this article Link to this article
Link to this article

CloseClose

Create a link to this page

Copy and paste this link tag into your Web page or blog:

<a href="http://www.encyclopedia.com/topic/.aspx#1E1-thulium" title="Facts and informations about thulium">thulium</a>

Add this article to Del.icio.usBookmark this article on DiigoShare this article on FacebookSubmit this article to RedditGive this article a thumbs-up on StumbleUpon
Show all research tools

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"thulium." The Columbia Encyclopedia, Sixth Edition. 2008. Encyclopedia.com. 10 Jul. 2009 <http://www.encyclopedia.com>.

"thulium." The Columbia Encyclopedia, Sixth Edition. 2008. Encyclopedia.com. (July 10, 2009). http://www.encyclopedia.com/doc/1E1-thulium.html

"thulium." The Columbia Encyclopedia, Sixth Edition. 2008. Retrieved July 10, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-thulium.html

Learn more about citation styles

thulium

World Encyclopedia | 2005 | © World Encyclopedia 2005, originally published by Oxford University Press 2005. (Hide copyright information) Copyright

thulium (symbol Tm) Lustrous, silver-white, metallic element of the lanthanide series (rare-earth metals). Its chief ore is monazite but thulium is as rare as gold. Soft, malleable and ductile, it combines with oxygen and the halogens. It is used in arc lighting and portable X-ray units. It is used in arc lighting and portable X-ray units. It was discovered in 1879 by Swedish chemist Per Cleve (1840–1905). Properties: at.no. 69; r.a.m. 168.9342; r.d. 9.31 (25°C); m.p. 1545°C (2813°F); b.p. 1947°C (3537°F); most stable isotope Tm169 (100%).

Hide all research tools
Print this article Print all entries for this topic Cite this article Link to this article
Link to this article

CloseClose

Create a link to this page

Copy and paste this link tag into your Web page or blog:

<a href="http://www.encyclopedia.com/topic/.aspx#1O142-thulium" title="Facts and informations about thulium">thulium</a>

Add this article to Del.icio.usBookmark this article on DiigoShare this article on FacebookSubmit this article to RedditGive this article a thumbs-up on StumbleUpon
Show all research tools

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"thulium." World Encyclopedia. 2005. Encyclopedia.com. 10 Jul. 2009 <http://www.encyclopedia.com>.

"thulium." World Encyclopedia. 2005. Encyclopedia.com. (July 10, 2009). http://www.encyclopedia.com/doc/1O142-thulium.html

"thulium." World Encyclopedia. 2005. Retrieved July 10, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-thulium.html

Learn more about citation styles

Tm

The Oxford Pocket Dictionary of Current English | 2009 | © The Oxford Pocket Dictionary of Current English 2009, originally published by Oxford University Press 2009. (Hide copyright information) Copyright

Tm • symb. the chemical element thulium.

Hide all research tools
Print this article Print all entries for this topic Cite this article Link to this article
Link to this article

CloseClose

Create a link to this page

Copy and paste this link tag into your Web page or blog:

<a href="http://www.encyclopedia.com/topic/.aspx#1O999-tm005" title="Facts and informations about thulium">thulium</a>

Add this article to Del.icio.usBookmark this article on DiigoShare this article on FacebookSubmit this article to RedditGive this article a thumbs-up on StumbleUpon
Show all research tools

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Tm." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 10 Jul. 2009 <http://www.encyclopedia.com>.

"Tm." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (July 10, 2009). http://www.encyclopedia.com/doc/1O999-tm005.html

"Tm." The Oxford Pocket Dictionary of Current English. 2009. Retrieved July 10, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-tm005.html

Learn more about citation styles

Free newspaper and magazine articles

Free Article StockerYale Inc.(The week that was)(Spectrode LLC)(Brief article)
Magazine article from: New Hampshire Business Review; 10/26/2007
Free Article Present Status of the Rare Earth Industry in China.
Magazine article from: China Chemical Reporter; 8/16/2001
Free Article Shiftgrams again.(word games)(Table)
Magazine article from: Word Ways; 2/1/2009

Facts and information from other sites

Related topics

  Edit this list
Tm
Tm

Related articles from newspapers, magazines, and more

StockerYale Inc.(The week that was)(Spectrode LLC)(Brief article)
Magazine article from: New Hampshire Business Review; 10/26/2007; 80 words ; StockerYale Inc. (STKR) has acquired the assets and intellectual property of Spectrode LLC, a developer of pulsed Thulium Doped Fiber Laser Technology. Under the terms of the transaction, all of Spectrode's patents and patents pending will be assigned... Read more
Present Status of the Rare Earth Industry in China.
Magazine article from: China Chemical Reporter; 8/16/2001; 700+ words ; ...the unique form of ion in China. They mainly include samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutecium and yttrium and elements such as lanthanum and neodymium. The reserves account for more than 90% of the... Read more
Shiftgrams again.(word games)(Table)
Magazine article from: Word Ways; 2/1/2009; ; 700+ words ; ...W3) nobelium 6 Oakhurst (place in California, various internet sites) oxygen 4 bricks (W3) thulium 6 Zonaras (a surname, various internet sites) thulium 10 swerved (W3) tin 5 sny (W3), syn (W3) tin 7 pau (W3) tin 13 vag (W3) tin 18 alf (W2) tin... Read more
Letter banks from the chemical elements.
Magazine article from: Word Ways; 11/1/2003; ; 700+ words ; ...lawrencium (Crumlinwallinwer Dickens) lead (deleaded) lithium (thulium) lutetium (telium) magnesium (unassumingnesses) manganese...terbium (imbrute) thallium (thalamium) thorium (hortorium) thulium (lithium) tin (nit) titanium (manitu) tungsten (ungets Web2... Read more
More elementary improvements.
Magazine article from: Word Ways; 5/1/2006; ; 448 words ; ...PHOSPHORUS--PHOSPHOROUS PROMETHIUM--PRIM-MOUTHED RUBIDIUM--MURUBINDI (Burundi) SELENIUM--LUMINESCE TECHNETIUM--MOUCHINETTE THULIUM--ITHUMULA (Kenya) TITANIUM--MILITAUNT (Haiti) Not included in Darryl's list: PROACTINIUM--PROTACTINIUM NON-OPTIMAL TRANSADDITIONS... Read more
Emerging Dental Technologies Update.
Magazine article from: Medical Equipment Designer; 3/1/2000; ; 700+ words ; ...the power supply, and composition of the lasing medium. The laser rod, or lasing medium, currently being tested uses erbium, thulium, and holmium added to a YAG crystal. Research and development is continuing to discem the correct combination of elements and... Read more
A magical pair of 6x6 chemical squares.
Magazine article from: Word Ways; 2/1/2004; ; 675 words ; ...Nitrogen Fluorine Silicon Argon Potassium Scandium Germanium Cadmium Indium Tin Xenon Barium Praseodymium Neodymium Erbium Thulium Lutetium Tantalum Rhenium Osmium Iridium Platinum Mercury Thallium Lead Actinium Thorium Protactinium Plutonium Einsteinium... Read more
The symbols of the chemical elements.
Magazine article from: Word Ways; 2/1/2002; ; 700+ words ; ...neodymium 61-65 Pm promethium Sm samarium Eu europium Gd gadolinium Tb terbium 66-70 Dy dysprosium Ho holmium Er erbium Tm thulium Yb ytterbium 71-75 Lu lutetium Hf hafnium Ta tantalum W tungsten Re rhenium 76-80 Os osmium Ir iridium Pt platinum Au gold... Read more

Pictures from Google Image Search

Click to see an enlarged picture
Click to see an enlarged picture
Click to see an enlarged picture

For students and teachers!

Encyclopedia.com provides students and teachers facts, information, and biographies from verified, citable sources, including:

Encyclopedia.com provides students and teachers facts, information, and biographies from verified, citable sources, including: