By: Emilio Mooney
Protactiniun And you
the atomic mass:231.036, number of protons 91, number of neutrons 140, number of electron 91.And there is no know boiling point for this element at this time. its natural phase is solid it coast $280.00 for one gram of protactinium. the classification is metal it received its name form the greek proton meaning first combined with Actinium,and was discovered by Kasimi jajans. Other important facts it is one the most rare metals in the world. this is very radioactive elements.