Praseodymium

Element 59 · Lanthanide

Specimen

Atomic number
59
Atomic mass
140.908
State at room temperature
Solid
Melting point
930.9 °C
Boiling point
3,520 °C
Density
6.77 g/cm³
Discovered
1885

Physical data from PubChem.1

Can I eat it?

In food and water
Not needed, little harm known. Praseodymium has no known function in the body. In rats, the dose of praseodymium chloride that killed half the animals was 4.5 g per kg of body weight. The RSC lists it as low in toxicity. There are few studies of it in food. 23

See every element.

The atom

Pr
ShellElectrons
1 (K) 2
2 (L) 8
3 (M) 18
4 (N) 21
5 (O) 8
6 (P) outermost 2
Total59

Configuration [Xe] 4f³ 6s²

4f ↑ ↑ ↑
6s ↑ ↓
A shell diagram: each ring is an electron shell and each dot is one electron. The nucleus holds 59 protons. The outermost shell is shown in red. Electrons do not travel on rings: they fill orbitals, regions where an electron is likely to be found. The boxes are those orbitals for the electrons outside the Xe core, with one arrow per electron.

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Sources

  1. 1

    National Center for Biotechnology Information (PubChem), 2026. Periodic Table of Elements .

    Atomic mass, electron configuration, melting and boiling points, density and discovery year for all 118 elements.

  2. 2

    Toxicology Excellence for Risk Assessment (TERA), for the US Bureau of Land Management, 1999. Development of Reference Doses and Reference Concentrations for Lanthanides , Section 2.4 (oral toxicity data in experimental animals).

    • 4500 mg/kg praseodymium chloride
  3. 3

    Royal Society of Chemistry, 2026. Praseodymium - Element information, properties and uses .

    • Praseodymium has no known biological role. It has low toxicity.