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Protactinium (Pa): Fun Facts And Information About The Element


What is the symbol? Pa
What is the atomic number? 91
What is the atomic weight? 231.0359
What is the melting point in Celsius?1568
What is the boiling point in Celsius?
What is the density (g/cm3)? 15.4
What year was it discovered? 1913
Who discovered the element? “Kasimir Fajans and O.H. Göhring”
What group is the element in? 102
What is the electron configuration? [Rn] 5f2 6d1 7s2
What is the ionization energy? 5.89
What element category is it in? Actinoids

Where Is Protactinium Found?

In 1934, from 0.1 g of pure Pa2O5 he isolated the element by two methods, one of which was by converting the oxide to an iodide and “cracking” it in a high vacuum by an electrically heated filament by the reaction: 2PaI5 –> 2Pa + 5I2.

What Is Protactinium Used For?

The element is a dangerous material and requires precautions similar to those used when handling plutonium. The elements is an alpha emitter (5.0 MeV) and is a radiological hazard similar to polonium.