Difference between revisions of "Dysprosium"
| Line 279: | Line 279: | ||
:4 Dy + 3 O<sub>2</sub> → 2 Dy<sub>2</sub>O<sub>3</sub> | :4 Dy + 3 O<sub>2</sub> → 2 Dy<sub>2</sub>O<sub>3</sub> | ||
| − | Dysprosium metal will slowly react with water, and far more quickly with mineral acids, at room temperature to release hydrogen: | + | Dysprosium metal will slowly react with water, and far more quickly with mineral acids, at room temperature to release [[hydrogen]]: |
:2 Dy + 6 H<sub>2</sub>O → 2 Dy(OH)<sub>3</sub> + 3 H<sub>2</sub> | :2 Dy + 6 H<sub>2</sub>O → 2 Dy(OH)<sub>3</sub> + 3 H<sub>2</sub> | ||
| Line 303: | Line 303: | ||
==Handling== | ==Handling== | ||
===Safety=== | ===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. | + | 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=== | ===Storage=== | ||
Revision as of 15:23, 5 June 2019
| General properties | |||||
|---|---|---|---|---|---|
| Name, symbol | Dysprosium, Dy | ||||
| Appearance | Silvery white | ||||
| Dysprosium in the periodic table | |||||
| |||||
| 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) | ||||
Dysprosium is a chemical element with the symbol Dy and atomic number 66. It is a silvery metal that is very slightly magnetic.
Contents
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 weak acids, like sulfamic acid or 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, 10 g for 30 $. 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 economical 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
No threads so far. Why not make one?
