39
  Y  
88.905850
Yttrium

Name: Yttrium
Symbol: Y
Atomic Number: 39
Atomic Weight: 88.905850
Family: Transition Metals
CAS RN: 7440-65-5
Description: Silvery metal, which is stable in air because of an oxide film that forms on its surface.
State (25 C): Solid
Oxidation states: +3

Molar Volume: 19.89 cm3/mole
Valence Electrons: 4d15s2

Boiling Point:  3611K, 3338C, 6040F
Melting Point:
1799K, 1526C, 2779F
Electrons Energy Level: 2, 8, 18, 9, 2
Isotopes: 31 + 1 Stable
Heat of Vaporization: 363 kJ/mol
Heat of Fusion: 11.4 kJ/mol
Density: 4.47 g/cm3 @ 300K
Specific Heat: 0.3 J/gK
Atomic Radius: 2.27
Ionic Radius: 0.9
Electronegativity: 1.22 (Pauling); 1.11 (Allrod Rochow)
Vapor Pressure: 5.31 Pa @ 1526C

1s2 2s2p6 3s2p6d10 4s2p6d1 5s2

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 Wohler 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 great 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 used for the most basic one and the others were re-named erbia and terbia.

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

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 400C.  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.  The current claim-to-fame for yttrium is its use in the so-called 1-2-3 oxide superconductors (along with barium and copper). These were the first superconducting materials to function at liquid nitrogen temperatures.

1s2
2s2 2p6
3s2 3p6 3d10
4s2 4p6 4d1
5s2

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 bastnasite (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.

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

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 include:

Yttrium has been studied for possible use as a nodulizer in the making of nodular cast iron which has increased ductility (the graphite forms compact nodules instead of flakes to form nodular cast iron).  Potentially, yttrium can be used in ceramic and glass formulas, since yttrium oxide has a high melting point and imparts shock resistance and low thermal expansion characteristics to glass.

Compounds

Although metallic yttrium is not widely used, several of its compounds are. Yttrium oxide (Y2O3) and yttrium orthovanadate (YVO4) are both combined with europium to produce the red phosphor used in color televisions. Garnets made from yttrium and iron (Y3Fe5O12) are used as microwave filters in microwave communications equipment. Garnets made from yttrium and aluminum (Y3Al5O12) are used in jewelry as simulated diamond.

Yttria, Y2O3 Yttrium Chloride, YCl3
Gadolinite, (Ce, La, Nd, Y)2FeBe2Si2O10

Isotopes

Natural yttrium is composed of only one stable 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 lifes 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.

atom.gif (700 bytes)

Isotope Atomic Mass Half-Life
Y77 76.95 < 1.2 ms
Y78 77.944 >150 ns
Y79 78.937 14.8 seconds
Y80 79.934 35 seconds
Y81 80.9291 70.4 seconds
Y82 81.927 9.5 seconds
Y83 82.9224 7.08 minutes
Y84 83.9204 4.6 seconds
Y85 84.9164 2.68 hours
Y86 85.9149 14.74 hours
Y87 86.9109 79.8 hours
Y88 87.9095 106.65 days
Y89 88.9059 Stable
Y90 89.9072 64 hours
Y91 90.907 58.51 days
Y92 91.9089 3.54 hours
Y93 92.9096 10.18 hours
Y94 93.9116 18.7 minutes
Y95 94.9128 10.3 minutes
Y96 95.9159 5.34 seconds
Y97 96.9181 3.75 seconds
Y98 97.9222 0.548 seconds
Y99 98.9246 1.470 seconds
Y100 99.9278 735 ms
Y101 100.93 0.45 seconds
Y102 101.9336 0.36 seconds
Y103 102.937 0.23 seconds
Y104 103.941 >150 ns
Y105 104.945 >150 ns
Y106 105.95 > 150 ns
Y107   ˜ 30 ms
Y108   20 ms

Precautions

40px-Skull_and_crossbones.svg.jpg (1420 bytes) 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.   Yttrium salts may be carcinogenic. 

This element is not normally found in human tissue and plays no known biological role.

80px-Flammable.jpg (2186 bytes) Yttrium metal is ductile and silvery. Powdered samples and turnings from machining can burst into flame.

 atom.gif (700 bytes)

Yttrium Data
 

Atomic Structure

  • Atomic Radius: 2.27
  • Atomic Volume: 19.8cm3/mol
  • Covalent Radius: 1.62
  • Cross Section (Thermal Neutron Capture) Barns: 1.28
  • Crystal Structure: Hexagonal
  • Electron Configuration:
    1s2 2s2p6 3s2p6d10 4s2p6d1 5s2
  • Electrons per Energy Level: 2, 8, 18, 9, 2
  • Ionic Radius: 0.9
  • Filling Orbital: 4d1
  • Number of Electrons (with no charge): 39
  • Number of Neutrons (most common/stable nuclide): 50
  • Number of Protons: 39
  • Oxidation States: 3
  • Valence Electrons: 4d1 5s2

Chemical Properties

  • Electrochemical Equivalent: 1.1057 g/amp-hr
  • Electron Work Function: 3.1eV
  • Electronegativity: 1.22 (Pauling); 1.11 (Allrod Rochow)
  • Heat of Fusion: 11.4 kJ/mol
  • Incompatibilities:
    Oxidizers
  • Ionization Potential
    • First: 6.38
    • Second: 12.24
    • Third: 20.52
  • Valence Electron Potential (-eV): 48

Physical Properties

  • Atomic Mass Average: 88.90585
  • Boiling Point: 3611K, 3338C, 6040F
  • Coefficient of Lineal Thermal Expansion/K-1: 10.6E-6
  • Conductivity
    Electrical: 0.0166 106/cm
    Thermal: 0.172 W/cmK
  • Density: 4.47 g/cm3 @ 300K
  • Description:
    Silvery metal, which is stable in air because of an oxide film that forms on its surface.
  • Elastic Modulus:
    • Bulk: 41/GPa
    • Rigidity: 25.5/GPa
    • Youngs: 66.3/GPa
  • Enthalpy of Atomization: 418 kJ/mole @ 25C
  • Enthalpy of Fusion: 17.15 kJ/mole
  • Enthalpy of Vaporization: 393 kJ/mole
  • Flammablity Class: Non-combustible solid (except as dust)
  • Freezing Point: see melting point
  • Hardness Scale
    • Brinell: 589 MN m-2
  • Heat of Vaporization: 363 kJ/mol
  • Melting Point: 1799K, 1526C, 2779F
  • Molar Volume: 19.89 cm3/mole
  • Physical State (at 20C & 1atm): Solid
  • Specific Heat: 0.3 J/gK
  • Vapor Pressure: 5.31 Pa @ 1526C

Regulatory / Health

  • CAS Number
    • 7440-65-5
  • RTECS: ZG2980000
  • OSHA Permissible Exposure Limit (PEL)
    • TWA: 1 mg/m3
  • OSHA PEL Vacated 1989
    • TWA: 1 mg/m3
  • NIOSH Recommended Exposure Limit (REL)
    • TWA: 1 mg/m3
    • IDLH: 500 mg/m3
  • Routes of Exposure: Inhalation; Ingestion; Skin and/or eye contact
  • Target Organs: Eyes, respiratory system, liver
  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm-3: 0.0047
    • Bone/p.p.m: 0.07
    • Liver/p.p.m: <0.01
    • Muscle/p.p.m: 0.02
    • Daily Dietary Intake: 0.016 mg
    • Total Mass In Avg. 70kg human: 0.6 mg

Who / Where / When / How

  • Discoverer: Johann Gadolin
  • Discovery Location: bo Finland
  • Discovery Year: 1794
  • Name Origin:
    From the town of Ytterby, Sweden.
  • Abundance:
    • Earth's Crust/p.p.m.: 30
    • Seawater/p.p.m.: 0.000009
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E12): 125
  • Sources:
    Found in xenotime, bastnasite, fergusonite and samarskite ores. Annual world wide production is around 400 tons. Primary mining areas are USA, Russia, Norway and Madagascar.
  • Uses:
    Combined with europium to make red phosphors for color TV's. Yttrium oxide and iron oxide combine to form a crystal garnet used in radars. Also used in lasers, camera lenses and fireproof bricks.

Ionization Energy (eV): 6.217 eV
Estimated Crustal Abundance: 3.3101 milligrams per kilogram
Estimated Oceanic Abundance:
1.310-5 milligrams per liter

atom.gif (700 bytes)

Transition Metals
Group 3
(IIIB)
4
(IVB)
5
(VB)
6
(VIB)
7
(VIIB)
8
(VIIIB)
9
(VIIIB)
10 (VIIIB) 11
(IB)
12
(IIB)
Period 4 21
Sc
44.95
22
Ti
47.86
23
V
50.94
24
Cr
51.99
25
Mn
54.93
26
Fe
55.84
27
Co
58.93
28
Ni
58.69
29
Cu
63.54
30
Zn
65.39
Period 5 39
Y
88.90
40
Zr
91.22
41
Nb
92.90
42
Mo
95.94
43
Tc
98.00
44
Ru
101.0
45
Rh
102.9
46
Pd
106.4
47
Ag
107.8
48
Cd
112.4
Period 6 57
La
138.9
72
Hf
178.4
73
Ta
180.9
74
W
183.8
75
Re
186.2
76
Os
190.2
77
Ir
192.2
78
Pt
195.0
79
Au
196.9
80
Hg
200.5
Period 7 89
Ac
227.0
104
Rf
261.0
105
Db
262.0
106
Sg
266.0
107
Bh
264.0
108
Hs
269.0
109
Mt
268.0
110
Ds
269.0
111
Rg
272.0
112
Uub
277.0

(Ytterby, a village in Sweden near Vauxholm) Yttria, which is an earth containing yttrium, was discovered by Gadolin in 1794. Ytterby is the site of a quarry which yielded many unusual minerals containing rare earths and other elements. This small town, near Stockholm, bears the honor of giving names to erbium, terbium, and ytterbium as well as yttrium. In 1843 Mosander showed that yttira could be resolved into the oxides (or earths) of three elements. The name yttria was reserved for the most basic one; the others were named erbia and terbia. Yttrium occurs in nearly all of the rare-earth minerals. Analysis of lunar rock samples obtained during the Apollo missions show a relatively high yttrium content. It is recovered commercially from monazite sand, which contains about 3%, and from bastnasite, which contains about 0.2%. Wohler obtained the impure element in 1828 by reduction of the anhydrous chloride with potassium. The metal is now produced commercially by reduction of the fluoride with calcium metal. It can also be prepared by other techniques. Yttrium has a silver-metallic luster and is relatively stable in air. Turnings of the metal, however, ignite in air if their temperature exceeds 400oC, and finely divided yttrium is very unstable in air. Yttrium oxide is one of the most important compounds of yttrium and accounts for the largest use. It is widely used in making YVO4 europium, and Y2O3 europium phosphors to give the red color in color television tubes. Many hundreds of thousands of pounds are now used in this application. Yttrium oxide also is used to produce yttrium-iron-garnets, which are very effective microwave filters. Yttrium iron, aluminum, and gadolinium garnets, with formulas such as Y3Fe5O12 and Y3Al5O12, have interesting magnetic properties. Yttrium iron garnet is also exceptionally efficient as both a transmitter and transducer of acoustic energy. Yttrium aluminum garnet, with a hardness of 8.5, is also finding use as a gemstone (simulated diamond). Small amounts of yttrium (0.1 to 0.2%) can be used to reduce the grain size in chromium, molybdenum, zirconium, and titanium, and to increase strength of aluminum and magnesium alloys. Alloys with other useful properties can be obtained by using yttrium as an additive. The metal can be used as a deoxidizer for vanadium and other nonferrous metals. The metal has a low cross section for nuclear capture. 90Y, one of the isotopes of yttrium, exists in equilibrium with its parent 90Sr, a product of nuclear explosions. Yttrium has been considered for use as a nodulizer for producing nodular cast iron, in which the graphite forms compact nodules instead of the usual flakes. Such iron has increased ductility. Yttrium is also finding application in laser systems and as a catalyst for ethylene polymerization. It also has potential use in ceramic and glass formulas, as the oxide has a high melting point and imparts shock resistance and low expansion characteristics to glass. Natural yttrium contains but one isotope, 89Y. Nineteen other unstable isotopes have been characterized. Yttrium metal of 99.9% purity is commercially available at a cost of about $75/oz.

Source: CRC Handbook of Chemistry and Physics, 1913-1995. David R. Lide, Editor in Chief. Author: C.R. Hammond