Symbol: Pa
Atomic number: 91
Atomic weight: (231)
Radioactive metallic element, belongs to the actinoids. The most stable isotope, Pa-231 has a half-life of 2.43*10^4 years. At least 10 other
radioactive isotopes are known. No practical applications are known. Discovered in 1917 by Lise Meitner and Otto Hahn.
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Sexual Intercour...
Prostatectomy
Protectionism
