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Protactinium is a chemical element; it has symbol Pa and atomic number 91. ... suggesting that actinium is a product of radioactive decay of protactinium.
Protactinium-231 is the longest-lived isotope of protactinium, with a half-life of 32,760 years. In nature, it is found in trace amounts as part of the actinium series , which starts with the primordial isotope uranium-235 ; the equilibrium concentration in uranium ore is 46.55 231 Pa per million 235 U.
Protactinyl nitrate, protactinium(V) oxynitrate, or erroneously known as protactinium nitrate, is a radioactive chemical compound with the formula PaO(NO 3) 3 ·xH 2 O (1.5 ≤ x ≤ 4). It is a white solid that readily hydrolyzes to protactinium(V) oxide in moist air. This compound is a common commercial source of protactinium. [2]
This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.
As protactinium(V) oxide, like other protactinium compounds, is radioactive, toxic and very rare, it has very limited technological use. Mixed oxides of Nb, Mg, Ga and Mn, doped with 0.005–0.52% Pa 2 O 5 , have been used as high temperature dielectrics (up to 1300 °C) for ceramic capacitors .
The actinide series is a group of chemical elements with atomic numbers ranging from 89 to 102, [note 1] including notable elements such as uranium and plutonium.The nuclides (or isotopes) thorium-232, uranium-235, and uranium-238 occur primordially, while trace quantities of actinium, protactinium, neptunium, and plutonium exist as a result of radioactive decay and (in the case of neptunium ...
Uranium-232 (232 U) is an isotope of uranium.It has a half-life of around 69 years and is a side product in the thorium cycle.It has been cited as an obstacle to nuclear proliferation using 233 U as the fissile material, because the intense gamma radiation emitted by 208 Tl (a daughter of 232 U, produced relatively quickly) makes the 233 U contaminated with it more difficult to handle.
Two mononuclidic, but radioactive elements (bismuth and protactinium) A mononuclidic element or monotopic element [1] is one of the 21 chemical elements that is found naturally on Earth essentially as a single nuclide (which may, or may not, be a stable nuclide). This single nuclide will have a characteristic atomic mass.