Difference between revisions of "Yttrium"

Revision as of 04:02, 15 June 2015

Yttrium is a transition metal with the symbol Y and the atomic number 39. It is chemically similar to the lanthanides, and is often grouped with them, as well as scandium, as a rare earth metal. Yttrium is a powerful reducing agent, but is not a necessary addition to the amateur chemistry lab when cheaper agents, such as magnesium, are readily available.

Properties

Physical properties

Yttrium is a silvery metal that is not very dense (comparable to titanium). It tends to form crystals which are hexagonally close-packed.

Chemical properties

Yttrium is a typical rare-earth metal, with similar chemistry to aluminium. It does not corrode in air, yet it has the highest thermodynamic affinity for oxygen of any element. Finely divided yttrium is prone to ignition. In solution, yttrium compounds do not exhibit any color due to the lack of free d or f electrons. Its standard reduction potential is almost exactly the same as that of magnesium. It reacts with acids to form salts, most of which are soluble except for yttrium fluoride and yttrium oxalate. Yttrium sulfate is only slightly soluble. The metal reacts with the halogens to produce trihalides.

Its primary oxidation state is +3. Yttrium(II) compounds exist, but are not accessible to the amateur.

Availability

Yttrium is more common than tin on Earth, but it is very hard to find and expensive (though relatively cheap for a rare-earth element). One source for yttrium, as well as other rare earth metals, is Metallium. It is sold in 5 gram and 50 gram sizes, as well as rods, ampoules, 100 gram ingots, and coins. Yttrium and its compounds occasionally sold on eBay as well.

Projects

• Yttrium thermite?
• Alloys with aluminium?

Safety

Toxicity

Toxicity data of yttrium compounds is scarce, but they appear to be of low to moderate danger. Yttrium plays no biological role, but acts similarly to calcium within the body. Some yttrium compounds, notably the halides, will hydrolyze when heated and will give off acidic vapors.

Flammability

Small pieces of yttrium metal or powder are flammable. Class D fire extinguishers should be readily available when working with yttrium near an open flame. Water should never be used to extinguish burning yttrium, as it will aggravate the flame.