Protaktinio (Pa) is a chemical element belonging to the category Inner transition metal, with atomic number 91 and atomic mass 231.0360 u. This sheet describes its fundamental properties, periodic position and physical characteristics.
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Astronomy · Chemical element
Protactinium
EL2J
Identity
Name: Protaktinio
Symbol: Pa
Atomic number: 91
Atomic mass: 231.0360 u
Position in the periodic table
Group: 3
Period: 7
Category: Inner transition metal
Physico-chemical properties
Standard state: Solid
Melting point: About 1572°C
Density: About 15.37 g/cm³
Electron configuration: [Rn] 5f² 6d¹ 7s²
Scientific description
Protaktinio is a chemical element with symbol Pa and atomic number 91.
It belongs to the category of Inner transition metal and occupies group 3 and period 7.
Its standard atomic mass is 231.0360 u.