Yttrium

Jump to: navigation, search
39 strontiumyttriumzirconium
Sc

Y

Lu
General
Name, Symbol, Number yttrium, Y, 39
Chemical series transition metals
Group, Period, Block 3, 5, d
Appearance silvery white
File:Y,39.jpg
Standard atomic weight 88.90585(2)  g·mol−1
Electron configuration [Kr] 4d1 5s2
Electrons per shell 2, 8, 18, 9, 2
Physical properties
Phase solid
Density (near r.t.) 4.472  g·cm−3
Liquid density at m.p. 4.24  g·cm−3
Melting point 1799 K
(1526 °C, 2779 °F)
Boiling point 3609 K
(3336 °C, 6037 °F)
Heat of fusion 11.42  kJ·mol−1
Heat of vaporization 365  kJ·mol−1
Heat capacity (25 °C) 26.53  J·mol−1·K−1
Vapor pressure
P(Pa) 1 10 100 1 k 10 k 100 k
at T(K) 1883 2075 (2320) (2627) (3036) (3607)
Atomic properties
Crystal structure hexagonal
Oxidation states 3, 2,[1] 1,[2]
(weakly basic oxide)
Electronegativity 1.22 (scale Pauling)
Ionization energies
(more)
1st:  600  kJ·mol−1
2nd:  1180  kJ·mol−1
3rd:  1980  kJ·mol−1
Atomic radius 180pm
Atomic radius (calc.) 212  pm
Covalent radius 162  pm
Miscellaneous
Magnetic ordering no data
Electrical resistivity (r.t.) (α, poly) 596 nΩ·m
Thermal conductivity (300 K) 17.2  W·m−1·K−1
Thermal expansion (r.t.) (α, poly)
10.6 µm/(m·K)
Speed of sound (thin rod) (20 °C) 3300 m/s
Young's modulus 63.5  GPa
Shear modulus 25.6  GPa
Bulk modulus 41.2  GPa
Poisson ratio 0.243
Brinell hardness 589  MPa
CAS registry number 7440-65-5
Selected isotopes
iso NA half-life DM DE (MeV) DP
87Y syn 3.35 d ε - 87Sr
γ 0.48, 0.38D -
88Y syn 106.6 d ε - 88Sr
γ 1.83, 0.89 -
89Y 100% Y is stable with 50 neutrons
90Y syn 2.67 d β- 2.28 90Zr
γ 2.18 -
91Y syn 58.5 d β- 1.54 91Zr
γ 1.20 -
References

Yttrium (pronounced /ˈɪtriəm/)[3], is a chemical element that has the symbol Y and atomic number 39. A silvery metallic transition metal, yttrium is common in rare-earth minerals and two of its compounds are used to make the red color phosphors in cathode ray tube displays, such as those used for televisions.

Notable characteristics

Yttrium is a silver-metallic, lustrous rare earth metal that is relatively stable in air, strongly resembles scandium in appearance, and chemically resembles the lanthanides, and can appear to gain a slight pink lustre on exposure to light. Shavings or turnings of the metal can ignite in air when they exceed 400 °C. When yttrium is finely divided, it is very unstable in air. The metal has a low neutron cross-section for nuclear capture. The common oxidation state of yttrium is +3.

Applications

Yttrium(III) oxide is the most important yttrium compound and is widely used to make YVO4:Eu and Y2O3:Eu phosphors that give the red color in color television picture tubes. Other uses:

History

Yttrium (named for Ytterby, a Swedish village near Vaxholm) was discovered by Finnish chemist, physicist, and mineralogist Johan Gadolin in 1794 and isolated by Friedrich Wöhler in 1828 as an impure extract of yttria through the reduction of yttrium anhydrous chloride (YCl3) with potassium. Yttria (Y2O3) is the oxide of yttrium and was discovered by Johan Gadolin in 1794 in a gadolinite mineral from Ytterby.

In 1843, the Swedish chemist Carl Mosander was able to show that yttria could be divided into the oxides (or earths) of three different elements. "Yttria" was the name which was retained for the most basic one, which also happened to comprise the bulk of the crude mixture (typically about two-thirds) and the others were re-named erbia and terbia. (Later in the 19th century, both of these would also be shown to be complex, although the names would be retained for the most characteristic component of each.)

A quarry is located near the village of Ytterby that yielded many unusual minerals that contained rare earths and other elements. The elements erbium, terbium, ytterbium, and yttrium have all been named after this same small village.

Occurrence

This element is found in almost all rare-earth minerals and in uranium ores but is never found in nature as a free element. Yttrium is commercially recovered from monazite sand (3% content, [(Ce, La, etc.)PO4]) and from bastnäsite (0.2% content, [(Ce, La, etc.)(CO3)F]). It is commercially produced by reducing yttrium fluoride with calcium metal but it can also be produced using other techniques. It is difficult to separate from other rare earths and when extracted, is a dark gray powder. The original "rare earths" ceria (1803) and yttria (1794) reflect the great geochemical divide that occurs between the light and heavy lanthanides due to "lanthanide contraction". The lighter lanthanides, with a larger radius, partition into minerals in sites with a higher coordination number (e.g. monazite), whereas the smaller heavy lanthanides prefer a slightly lower coordination number (as in xenotime). The lighter lanthanides are also more relatively abundant in the earth's outer crust than the heavies, relative to the abundance in chondritic meteorites, due to size fractionation. Yttrium falls into the middle of the heavy group in size, and thus inevitably occurs with these in minerals, where it comprises about two-thirds of the mixed oxides by weight. This composition is typical of gadolinite, xenotime, and certain ion adsorption clays currently mined in the south of China.

Lunar Rock samples from the Apollo program have a relatively high yttrium content.

See also yttrium minerals.

Isotopes

Natural yttrium is composed of only one isotope (Y-89). The most stable radioisotopes are Y-88 which has a half life of 106.65 days and Y-91 with a half life of 58.51 days. All the other isotopes have half lives of less than a day except Y-87 which has a half life of 79.8 hours. The dominant decay mode below the stable Y-89 is electron capture and the dominant mode after it is beta emission. Twenty six unstable isotopes have been characterized.

Y-90 exists in equilibrium with its parent isotope strontium-90, which is a product of nuclear explosions.

Precautions

Compounds that contain this element are rarely encountered by most people but should be considered to be highly toxic even though many compounds pose little risk[citation needed]. Yttrium salts may be carcinogenic[citation needed]. This element is not normally found in human tissue and plays no known biological role.

See also

References

  1. "Yttrium: yttrium(II) hydride compound data". WebElements.com. Retrieved 2007-12-10.
  2. "Yttrium: yttrium(I) bromide compound data". OpenMOPAC.net. Retrieved 2007-12-10.
  3. Sound file - pronunciation [1]

External links

af:Yttrium az:İttrium bn:ইট্রিয়াম be:Ітрый bs:Itrijum ca:Itri cs:Yttrium co:Ittriu da:Yttrium de:Yttrium et:Ütrium el:Ύτριο eo:Itrio eu:Itrio fa:ایتریوم fur:Itri gl:Itrio ko:이트륨 hy:Իտրիում hi:इत्रियम hr:Itrij io:Yitrio id:Itrium is:Yttrín it:Ittrio he:איטריום sw:Ytri ku:Îtriyûm la:Yttrium lv:Itrijs lb:Yttrium lt:Itris jbo:jinmrtitri hu:Ittrium nl:Yttrium no:Yttrium nn:Yttrium oc:Itri uz:Ittriy qu:Itriyu scn:Ittriu simple:Yttrium sk:Ytrium sl:Itrij sr:Итријум sh:Itrijum fi:Yttrium sv:Yttrium ta:யிற்றியம் th:อิตเทรียม uk:Ітрій


Linked-in.jpg