ProtactiniumProtactinium’s of protactinium. Therefore, protactinium means “before actinium.”

 ProtactiniumProtactinium’s origin derives from the Greek word “protos,” meaning first, and the element actinium. Actinium being the product of the radioactive decay of protactinium. Therefore, protactinium means “before actinium.” Atomic number = 91 Symbol = PaAverage atomic mass = 231.03588A neutral protactinium atom contains 2 valence electrons. Protactinium is a metal, ergo, it is centered in the periodic table and located within the seventh column. This property signifies elements such as praseodymium, seaborgium, tungsten, molybdenum, and chromium share similar physical and chemical properties to protactinium. In nature, minuscule amounts of protactinium are commonly extracted from uranium ores. Due to its toxic radioactivity, protactinium is rarely used, asides from during research. Compounds of ProtactiniumDue to protactinium’s high reactivity to the halogens, various compounds may be formed with fluorine, chlorine, bromine, iodine, etc. For instance, these compounds include protactinium bromide, protactinium chloride, protactinium fluoride, protactinium iodide, and protactinium oxide. Based on protactinium’s rareness, it’s compounds are often human-made. Protactinium Bromide = PaBr5Protactinium Chloride = PaCl5Protactinium Flouride = PaF5Protactinium Iodide = PaI5Protactinium Oxide = PaODiscovery of ProtactiniumKasimir Fajans and O.H. Gohring were the first to discover protactinium in 1913, whilst examining uranium’s states of decay. They had discovered the protactinium-234 isotope. In 1918, two groups of scientists, Otto Hahn and Lise Meitner of Germany and Frederick Soddy and John Cranston of Great Britain, discovered another isotope of protactinium, protactinium-231. Aristid V. Grosse finally isolated protactinium in 1934. Protactinium is amongst the rarest and most expensive elements of the periodic table. Works CitedThomas Jefferson National Accelerator Facility – Office of Science Education. “It’s Elemental.” It’s Elemental – The Element Protactinium. Jefferson Lab, n.d. Web. 26 Jan. 2018. .Morss, Lester. “Protactinium.” Encyclopædia Britannica. Encyclopædia Britannica, inc., 24 Jan. 2018. Web. 26 Jan. 2018. .Staff, Live Science. “Facts About Protactinium.” LiveScience. Purch, 17 Sept. 2013. Web. 26 Jan. 2018. .K., Maggie, and Kirsten S. “Protactinium.” #91 – Protactinium – Pa. N.p., n.d. Web. 26 Jan. 2018. .”PROTACTINIUM.” Chemistry Explained. Advameg, Inc., n.d. Web. 26 Jan. 2018. .