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| quote: | Originally posted by Ste
PA means many things, perhaps you should elaborate! |
Procrastinators Anonymous!
I'm gonna join... soon.
Or alternatively...
Name: Protactinium
Atomic Number: 91
Symbol: Pa
Atomic weight: 231.0359
The atomic weight of protactinium is 231.0359, its melting point is < 1600°C, specific gravity has been calculated to be 15.37, with a valence of 4 or 5. Protactinium has a bright metallic luster which is retained for a while in air. The element is superconductive below 1.4K. Several protactinium compounds are known, some of which are colored. Protactinium is an alpha emitter (5.0 MeV) and is a radiological hazard which requires special handling. Protactinium is one of the rarest and most expensive naturally occurring elements.
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"I expect to pass through life but once. If therefore, there be any kindness I can show, or any good thing I can do to any fellow being, let me do it now, and not defer or neglect it, as I shall not pass this way again."
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