promethium

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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]

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]