promethium


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Related to promethium: Prometrium

promethium

 (Pm) [pro-me´the-um]
a chemical element, atomic number 61, atomic weight 147. (See Appendix 6.)

pro·me·thi·um (Pm),

(prō-mē'thē-ŭm),
A radioactive element of the rare earth series, atomic no. 61; first chemically identified in 1945; 145Pm has the longest known half-life (17.7 years).
[Prometheus, a Titan of G. myth who stole fire to give to mortals]

promethium

/pro·me·thi·um/ (Pm) (-me´the-um) chemical element, at. no. 61.

promethium (Pm)

[-mē′thē·əm]
Etymology: L, Prometheus, mythic character who gave fire to humans
a radioactive rare earth metallic element. Its atomic number is 61; its atomic mass is 145.

pro·me·thi·um

(Pm) (prŏ-mē'thē-ŭm)
A radioactive element of the rare earth series, atomic no. 61; 145Pm has the longest known half-life (17.7 years).
[prometheus, a Titan of G. myth who stole fire to give to mortals]

promethium

a chemical element, atomic number 61, atomic weight 147, symbol Pm. See Table 6.
References in periodicals archive ?
When all fourteen lanthanides are considered, except promethium trichloride, there is no simple explanation for [T.
With the discovery of promethium, the periodic table had no further gaps, and all that remained was to discover further elements beyond the now-known curium (element number 96).
Less well-known is the promethium, atomic number 61, in the paint on an old compass.