Protactinium (Pa)

About Protactinium

Protactinium is a chemical element with the symbol Pa and atomic number 91, meaning every atom has 91 protons in its nucleus. It is classed as Actinide and is a solid at room temperature. Its atomic mass is about 231.036 atomic mass units (u).

On the periodic table, Protactinium sits in group 5, period 7 (actinide series), which determines how many electron shells it has and how it tends to react with other elements.

Uses of Protactinium

In daily life and industry, Protactinium is used for Radioactive. These uses are closely tied to the typical properties of elements in the Actinide category.

Electron Structure of Protactinium

Using a simplified electron shell model (at most 2 electrons in the first shell, 8 in the second, 18 in the third, and so on), Protactinium has 5 electron shells, with an approximate arrangement of 2, 8, 18, 32, 31 electrons from the innermost shell to the outermost. This is a simplified learning model, not the full electron configuration that accounts for the s, p, d and f subshells.

Explore Other Elements

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