protactinium (Pa)

Term: protactinium (Pa)

Literally meaning: “before actinium”

Origin

πρώτος/protos(=first or of prime importance)

'áκτίς actis(genitive áκτ[éνος/actinos)(=ray, beam)

The name was given in order to reflect the product of the decay process.

Coined/History 

The element was discovered by Polish chemist Kasimir Fajans (1887-1975) and German chemist Oswald Gohring in 1913 by studying uranium’decay chain. They named the element “brevium” meaning brief because the short half-life (1.17 minutes) of the isotope that they found. Protactinium was first isolated by Russian born American nuclear chemist Aristid V. Grosse in 1934 (1905-1985).

§                    Oswald Helmuth Göhring: Über das neue Element Brevium und Versuche zur Auffindung seiner Isotopen. (Acerca del nuevo elemento brevium y los intentos de localizar sus isótopos). Tesis doctoral, Technischen Hochschule Fridericiana zu Karlsruhe, 1914. 58 pág.⁶

§                    K. Fajans and O. H. Göhring, "Über das Uran X2-das neue Element der Uranreihe". ("Sobre el Uranio X2, el nuevo elemento de la serie del uranio") Phys. Zeitschrift, 1913, 14, 877–84.

Definition

Protactinium is a silvery-grey metallic and radioactive chemical element with atomic number  91 and atomic mass 231.03588.