Lexic.us

Definition of Thorium

1. Noun. A soft silvery-white tetravalent radioactive metallic element; isotope 232 is used as a power source in nuclear reactors; occurs in thorite and in monazite sands.

Definition of Thorium

1. n. A metallic element found in certain rare minerals, as thorite, pyrochlore, monazite, etc., and isolated as an infusible gray metallic powder which burns in the air and forms thoria; -- formerly called also thorinum. Symbol Th. Atomic weight 232.0.

Definition of Thorium

1. Noun. a chemical element (''symbol'' Th) with atomic number 90. ¹

¹ Source: wiktionary.com

Definition of Thorium

1. a metallic element [n -S]

Medical Definition of Thorium

1. A metallic element found in certain rare minerals, as thorite, pyrochlore, monazite, etc, and isolated as an infusible gray metallic powder which burns in the air and forms thoria; formerly called also thorinum. Symbol Th. Atomic weight 232.0. Origin: NL. See Thorite. Source: Websters Dictionary (01 Mar 1998)

Lexicographical Neighbors of Thorium

Literary usage of Thorium

Below you will find example usage of this term as found in modern and/or classical literature:

1. The Encyclopedia Americana: A Library of Universal Knowledge (1919)
"The excited activity of thorium falls to half value in 11 hours, ... It was found that an intensely active substance called thorium X could be separated by ..."

2. The Encyclopedia Americana: A Library of Universal Knowledge (1919)
"The excited activity of thorium falls to half value in 11 hours, ... It was found that an intensely active substance called thorium X could be separated by ..."

3. A Treatise on Chemistry by Henry Enfield Roscoe, John Cannell Cain, Carl Schorlemmer (1913)
"thorium. 662 As already mentioned, the radioactivity of thorium was discovered by Schmidt and by Mme. Curie, and the existence of an emanation by Rutherford ..."

4. Standard Methods of Chemical Analysis: A Manual of Analytical Methods and by Wilfred Welday Scott (1922)
"Heat to 60°-80° C. and precipitate the thorium with 20 cc. of pure 3% H2C>2 solution ... The thorium is then determined by boiling off the emanations in a ..."

5. Radioactive substances and their radiations by Ernest Rutherford (1913)
"thorium AND ITS PRODUCTS. 216. We have given in Section 4 a brief ... In this chapter, the long series of transformations occurring in thorium will be ..."

6. A Text-book of Physics by William Watson (1911)
"This theory was first put forward by Rutherford and Soddy to explain the results of their experiments on thorium. These observers found that the ..."

7. The Chemistry of the Radio-elements by Frederick Soddy (1911)
"thorium emanation, for which radio-thorium is pre-eminently suitable, ... thorium X Period of average life—5.35 days. Period of half-change—3.7 days. ..."

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