Dysprosium

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Dysprosium,  66Dy
General properties
Name, symbol Dysprosium, Dy
Appearance Silvery white
Dysprosium in the periodic table


Dy

Cf
TerbiumDysprosiumHolmium
Atomic number 66
Standard atomic weight (Ar) 162.500(1)
Group, block , f-block
Period period 6
Electron configuration [Xe] 4f10 6s2
per shell
2, 8, 18, 28, 8, 2
Physical properties
Silvery-white
Phase Solid
Melting point 1680 K ​(1407 °C, ​​2565 °F)
Boiling point 2840 K ​(2562 °C, ​4653 °F)
Density near r.t. 8.54 g/cm3
when liquid, at  8.37 g/cm3
Heat of fusion 11.06 kJ/mol
Heat of 280 kJ/mol
Molar heat capacity 27.7 J/(mol·K)
 pressure
Atomic properties
Oxidation states 4, 3, 2, 1 ​​(a weakly basic oxide)
Electronegativity Pauling scale: 1.22
energies 1st: 573 kJ/mol
2nd: 1130 kJ/mol
3rd: 2200 kJ/mol
Atomic radius empirical: 178 pm
Covalent radius 192±7 pm
Miscellanea
Crystal structure ​Hexagonal close-packed (hcp)
Speed of sound thin rod 2710 m/s (at 20 °C)
Thermal expansion 9.9 µm/(m·K) (α, poly)
Thermal conductivity 10.7 W/(m·K)
Electrical resistivity 926·10-9 Ω·m (at 20 °C) (α, poly)
Magnetic ordering Paramagnetic
Young's modulus 61.4 GPa (α, poly)
Shear modulus 24.7 GPa (α, poly)
Bulk modulus 40.5 GPa (α, poly)
Poisson ratio 0.247 (α, poly)
Vickers hardness 410–550 MPa
Brinell hardness 500–1050 MPa
CAS Registry Number 7429-91-6
History
Discovery Lecoq de Boisbaudran (1886)
· references

Dysprosium is a chemical element with the symbol Dy and atomic number 66. It is a silvery metal that is very slightly magnetic.

Properties

Chemical

Dysprosium metal burns readily to form dysprosium(III) oxide:

4 Dy + 3 O2 → 2 Dy2O3

Dysprosium metal will slowly react with water, and far more quickly with mineral acids, at room temperature to release hydrogen:

2 Dy + 6 H2O → 2 Dy(OH)3 + 3 H2

However, dysprosium dissolves only slowly in sulfamic acid and citric acid, even when concentrated.

Physical

Dysprosium is a silvery lanthanide metal. It is soft enough to be scratched with a knife (though cutting it with a knife is time-consuming), and can be machined without sparking if overheating is avoided. Dysprosium and holmium have the highest magnetic strengths of the elements, especially at low temperatures. When cooled with liquid nitrogen, the metal turns ferromagnetic from its usual strong paramagnetic state.

Most dysprosium salts are highly paramagnetic. Some are also fluorescent.

Availability

Dysprosium is readily available from source such as Metallium and eBay. United Nuclear also sells metallic dysprosium, at 30 $/10g. It is not cheap, but it is less expensive than gold or other precious metals.

Preparation

Metallic dysprosium can be prepared by reducing dysprosium halides with calcium or lithium. However, it is far more feasible to just buy the metal.

Projects

  • Dysprosium nitrate
  • Make yellow fluorescent salts
  • Dysprosium phthalate coordination polymer?

Handling

Safety

Dysprosium will react with water to produce hydrogen, which is flammable. Soluble dysprosium salts, such as dysprosium chloride and dysprosium nitrate, are mildly toxic when ingested. The insoluble salts, however, are non-toxic. Dysprosium fires require a class D fire extinguisher. Water may aggravate dysprosium fires or cause a hydrogen explosion.

Storage

Dysprosium can be stored in air indefinitely without any significant corrosion, likely due to passivation. Argon and mineral oil can be used to store it for very long periods of time. Water, acids, and any metal cleaning agent will tarnish dysprosium.

Disposal

As dysprosium is expensive, it's best to try to recycle it.

References

Relevant Sciencemadness threads

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