Protactinium

=Protactinium= = = By: Maximilian


 * Atomic Number:** 91


 * Protons:** 91


 * Electrons:** 91


 * Neutrons:** 140


 * Average Atomic Mass: 231.03587 amu**


 * Isotopes:** pa-230, pa-231, pa-233, pa-234, pa-234m


 * Discovery:** Protactinium was discovered in 1917 by Fredrich Soddy.


 * Name:** Protactinium is named after the greek word protas meaning first.


 * Uses: There are no known uses yet.**


 * Interesting Facts**: The Classification of protactinium is Rare Earth. T he Crystal Structure is Orthorhombic


 * Video:** media type="youtube" key="3nZB4u34q98" height="385" width="480"

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 * Sources**
 * Photo: http://www.periodictable.com/Elements/091/index.html
 * Video: http://www.youtube.com/watch?v=3nZB4u34q98
 * http://www.webelements.com/protactinium/
 * http://www.chemicalelements.com/elements/pa.html