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protactinium    
n. 镤

镤

protactinium
n 1: a short-lived radioactive metallic element formed from
uranium and disintegrating into actinium and then into lead
[synonym: {protactinium}, {protoactinium}, {Pa}, {atomic number
91}]

Protactinium \Protactinium\
The radioactive chemical element, of atomic number 91; Atomic
symbol Pa; at. wt. of longest-lived isotope, 231 (T1/2 =
32,500 yrs.) Also called brevium, Uranium X2 and UX2.
[PJC]


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  • Protactinium - Wikipedia
    Protactinium is a chemical element; it has symbol Pa and atomic number 91 It is a dense, radioactive, silvery-gray actinide metal which readily reacts with oxygen, water vapor, and inorganic acids It forms various chemical compounds, in which protactinium is usually present in the oxidation state +5, but it can also assume +4 and even +3 or +2 states Concentrations of protactinium in the
  • NYT Connections Hints And Answers For Friday, May 29 - Forbes
    Looking for today's NYT Connections hints? Some help and the answers for today's game are right here to help keep your streak alive
  • Protactinium - Element information, properties and uses | Periodic Table
    Element Protactinium (Pa), Group 20, Atomic Number 91, f-block, Mass 231 036 Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images
  • Protactinium | Radioactive, Decay, Isotopes | Britannica
    Protactinium (Pa), radioactive chemical element of the actinoid series of the periodic table, rarer than radium; its atomic number is 91 It occurs in all uranium ores to the extent of 0 34 part per million of uranium Its existence was predicted by Russian chemist Dmitry Mendeleyev in his 1871
  • Periodic Table of Elements: Los Alamos National Laboratory
    Protactinium metal is a dense, silvery-gray material with a bright metallic luster which it retains for some time in air but it does readily react with oxygen, water vapor and inorganic acids to form various compounds In solid compounds protactinium is most stable in the oxidation state +5, but it also exists in the +4, +3 and +2 oxidation states
  • Protactinium: Element Properties and Uses - samaterials. com
    Protactinium is a rare radioactive actinide element exhibiting unique chemical and physical properties, fueling scientific research and specialized industrial applications globally
  • Protactinium Facts - Symbol Pa or Atomic Number 91
    Protactinium is a dense, silvery-gray metallic element with the symbol Pa and atomic number 91 It is a radioactive actinide found in trace amounts in uranium ores Protactinium is one of the rarest naturally occurring elements in Earth’s crust and has limited commercial applications due to its scarcity, toxicity, and intense radioactivity However, it has important scientific uses in
  • Isotopes of protactinium - Wikipedia
    Protactinium-231 is the longest-lived isotope of protactinium, [15] with a half-life of 32,760 years [16][17] In nature, it is found in trace amounts as part of the actinium series, [17][18] which starts with the primordial isotope uranium-235; [19] the equilibrium concentration in uranium ore is 46 5 atoms of 231 Pa per million of 235 U
  • Protactinium | Pa (Element) - PubChem
    Chemical element, Protactinium, information from authoritative sources Look up properties, history, uses, and more
  • Protactinium Facts, Symbol, Discovery, Properties, Uses
    What is Protactinium Protactinium is a highly radioactive metal belonging to the family of actinides and denoted by the chemical symbol Pa [1] It has 27 isotopes with mass numbers ranging from 212 to 238 out of which protactinium-231 is the most stable one with a half-life of 3 276 x 10 4 years After which, it forms actinium -277 through alpha decay [3]





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