Praseodymium

Praseodymium is a chemical element with the atomic number 59 and symbol Pr.

Properties

Chemical

Praseodymium metal tarnishes slowly in air and burns readily at 150 °C to form praseodymium(III,IV) oxide:

12 Pr + 11 O₂ → 2 Pr₆O₁₁

It is somewhat more resistant to corrosion in air than most lanthanides, such as europium, lanthanum, cerium, or neodymium. It will slowly build-up a green oxide coating that spalls off when exposed to air, exposing more metal to oxidation.

Physical

Praseodymium is a silvery, soft, malleable, and ductile lanthanide metal. It will slowly oxidize in air, giving the metal a greenish aspect. It melts at 935 °C and boils at 3130 °C. Its density is 6.77 g/cm³.

Availability

Praseodymium is sold by Metallium and can also be purchased from Ebay.

Preparation

Reducing praseodymium salts with a reactive metal such as calcium or magnesium yields metallic praseodymium.

Projects

• Praseodymium yellow-green glass
• Make didymium
• Make PrNi₅ alloy

Handling

Safety

Like all lanthanides, praseodymium has low to moderate toxicity. It has no known biological role.

Storage

In closed bottles or ampoules, away from moisture or corrosive vapors.

Disposal

Best to try to recycle it.

References

Relevant Sciencemadness threads

• Praseodymium Oxide