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The Element Protactinium


"The Atom"

Definition of the Protactinium Element

A short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into Lead. It does not tarnish rapidly in air, it is attacked by Oxygen, steam and acids, but not by alkalis. It is superconductive at temperatures below 1.4 K. The Atomic Number of this element is 91 and the Element Symbol is Pa.

The Properties of the Protactinium Element
Symbol: Pa
Atomic Number: 91
Atomic Mass: 231.03587 amu
Melting Point: 1600.0 C - 1873.15 K
Boiling Point: Unknown
Number of Protons/Electrons: 91
Number of Neutrons: 140
Crystal Structure: Orthorhombic
Density @ 293 K: 15.4 g/cm3
Color: silver

Origin / Meaning of the name Protactinium
The name originates from the Greek word 'protos' meaning first and actinium, since it was found to be the parent of actinium.

Periodic Table Group and Classification of the of the Protactinium Element
Elements can be classified based on their physical states (States of Matter) e.g. gas, solid or liquid. This element is a solid. Protactinium is classified as an element in the Actinide series as one of the "Rare Earth Elements" which can located in Group 3 elements of the Periodic Table and in the 6th and 7th periods. The Rare Earth Elements are of the Lanthanide and Actinide series. Most of the elements in the Actinide series are synthetic or man-made. Nearly 75% of all the elements in the Periodic Table are classified as metals which are detailed in the List of Metals.

Facts about the Discovery and History of the Protactinium Element
Protactinium was discovered by Fredrich Soddy  in 1917.

Occurrence of the Protactinium Element
Obtained from fission product of plutonium, uranium & thorium,

Abundances of the element in different environments
% in Universe N/A
% in Sun N/A
% in Meteorites N/A
% in Earth's Crust 9.910-13%
% in Oceans 210-23%
% in Humans None

Associated Uses of Protactinium
Basic scientific research

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