Difference between revisions of "Platinum"
(12 intermediate revisions by 2 users not shown) | |||
Line 1: | Line 1: | ||
− | '''Platinum''' is a chemical element with the chemical symbol '''Pt'''. It is a transition metal, part of the so called "platinum | + | {{Infobox element |
+ | <!-- top --> | ||
+ | |image name= | ||
+ | |image alt= | ||
+ | |image size= | ||
+ | |image name comment= | ||
+ | |image name 2= | ||
+ | |image alt 2= | ||
+ | |image size 2= | ||
+ | |image name 2 comment= | ||
+ | <!-- General properties --> | ||
+ | |name=Platinum | ||
+ | |symbol=Pt | ||
+ | |pronounce= | ||
+ | |pronounce ref= | ||
+ | |pronounce comment= | ||
+ | |pronounce 2= | ||
+ | |alt name= | ||
+ | |alt names= | ||
+ | |allotropes= | ||
+ | |appearance=Silvery white metal | ||
+ | <!-- Periodic table --> | ||
+ | |above=[[Palladium|Pd]] | ||
+ | |below=Ds | ||
+ | |left=[[Iridium]] | ||
+ | |right=[[Gold]] | ||
+ | |number=78 | ||
+ | |atomic mass=195.084(9) | ||
+ | |atomic mass 2= | ||
+ | |atomic mass ref= | ||
+ | |atomic mass comment= | ||
+ | |series= | ||
+ | |series ref= | ||
+ | |series comment= | ||
+ | |series color= | ||
+ | |group=10 | ||
+ | |group ref= | ||
+ | |group comment= | ||
+ | |period=6 | ||
+ | |period ref= | ||
+ | |period comment= | ||
+ | |block=d | ||
+ | |block ref= | ||
+ | |block comment= | ||
+ | |electron configuration=[Xe] 4f<sup>14</sup> 5d<sup>9</sup> 6s<sup>1</sup> | ||
+ | |electron configuration ref= | ||
+ | |electron configuration comment= | ||
+ | |electrons per shell=2, 8, 18, 32, 17, 1 | ||
+ | |electrons per shell ref= | ||
+ | |electrons per shell comment= | ||
+ | <!-- Physical properties --> | ||
+ | |physical properties comment= | ||
+ | |color=Silvery-white | ||
+ | |phase=Solid | ||
+ | |phase ref= | ||
+ | |phase comment= | ||
+ | |melting point K=2041.4 | ||
+ | |melting point C=1768.3 | ||
+ | |melting point F=3214.9 | ||
+ | |melting point ref= | ||
+ | |melting point comment= | ||
+ | |boiling point K=4098 | ||
+ | |boiling point C=3825 | ||
+ | |boiling point F=6917 | ||
+ | |boiling point ref= | ||
+ | |boiling point comment= | ||
+ | |sublimation point K= | ||
+ | |sublimation point C= | ||
+ | |sublimation point F= | ||
+ | |sublimation point ref= | ||
+ | |sublimation point comment= | ||
+ | |density gplstp= | ||
+ | |density gplstp ref= | ||
+ | |density gplstp comment= | ||
+ | |density gpcm3nrt=21.45 | ||
+ | |density gpcm3nrt ref= | ||
+ | |density gpcm3nrt comment= | ||
+ | |density gpcm3nrt 2= | ||
+ | |density gpcm3nrt 2 ref= | ||
+ | |density gpcm3nrt 2 comment= | ||
+ | |density gpcm3nrt 3= | ||
+ | |density gpcm3nrt 3 ref= | ||
+ | |density gpcm3nrt 3 comment= | ||
+ | |density gpcm3mp=19.77 | ||
+ | |density gpcm3mp ref= | ||
+ | |density gpcm3mp comment= | ||
+ | |density gpcm3bp= | ||
+ | |density gpcm3bp ref= | ||
+ | |density gpcm3bp comment= | ||
+ | |molar volume= | ||
+ | |molar volume unit = | ||
+ | |molar volume ref= | ||
+ | |molar volume comment= | ||
+ | |triple point K= | ||
+ | |triple point kPa= | ||
+ | |triple point ref= | ||
+ | |triple point comment= | ||
+ | |triple point K 2= | ||
+ | |triple point kPa 2= | ||
+ | |triple point 2 ref= | ||
+ | |triple point 2 comment= | ||
+ | |critical point K= | ||
+ | |critical point MPa= | ||
+ | |critical point ref= | ||
+ | |critical point comment= | ||
+ | |heat fusion=22.17 | ||
+ | |heat fusion ref= | ||
+ | |heat fusion comment= | ||
+ | |heat fusion 2= | ||
+ | |heat fusion 2 ref= | ||
+ | |heat fusion 2 comment= | ||
+ | |heat vaporization=510 | ||
+ | |heat vaporization ref= | ||
+ | |heat vaporization comment= | ||
+ | |heat capacity=25.86 | ||
+ | |heat capacity ref= | ||
+ | |heat capacity comment= | ||
+ | |heat capacity 2= | ||
+ | |heat capacity 2 ref= | ||
+ | |heat capacity 2 comment= | ||
+ | |vapor pressure 1=2330 | ||
+ | |vapor pressure 10=(2550) | ||
+ | |vapor pressure 100=2815 | ||
+ | |vapor pressure 1 k=3143 | ||
+ | |vapor pressure 10 k=3556 | ||
+ | |vapor pressure 100 k=4094 | ||
+ | |vapor pressure ref= | ||
+ | |vapor pressure comment= | ||
+ | |vapor pressure 1 2= | ||
+ | |vapor pressure 10 2= | ||
+ | |vapor pressure 100 2= | ||
+ | |vapor pressure 1 k 2= | ||
+ | |vapor pressure 10 k 2= | ||
+ | |vapor pressure 100 k 2= | ||
+ | |vapor pressure 2 ref= | ||
+ | |vapor pressure 2 comment= | ||
+ | <!-- Atomic properties --> | ||
+ | |atomic properties comment= | ||
+ | |oxidation states=6, 5, '''4''', 3, '''2''', 1, −1, −2, −3 | ||
+ | |oxidation states ref= | ||
+ | |oxidation states comment=(a mildly basic oxide) | ||
+ | |electronegativity=2.28 | ||
+ | |electronegativity ref= | ||
+ | |electronegativity comment= | ||
+ | |ionization energy 1=870 | ||
+ | |ionization energy 1 ref= | ||
+ | |ionization energy 1 comment= | ||
+ | |ionization energy 2=1791 | ||
+ | |ionization energy 2 ref= | ||
+ | |ionization energy 2 comment= | ||
+ | |ionization energy 3= | ||
+ | |ionization energy 3 ref= | ||
+ | |ionization energy 3 comment= | ||
+ | |number of ionization energies= | ||
+ | |ionization energy ref= | ||
+ | |ionization energy comment= | ||
+ | |atomic radius=139 | ||
+ | |atomic radius ref= | ||
+ | |atomic radius comment= | ||
+ | |atomic radius calculated= | ||
+ | |atomic radius calculated ref= | ||
+ | |atomic radius calculated comment= | ||
+ | |covalent radius=136±5 | ||
+ | |covalent radius ref= | ||
+ | |covalent radius comment= | ||
+ | |Van der Waals radius=175 | ||
+ | |Van der Waals radius ref= | ||
+ | |Van der Waals radius comment= | ||
+ | <!-- Miscellanea --> | ||
+ | |crystal structure= | ||
+ | |crystal structure prefix= | ||
+ | |crystal structure ref= | ||
+ | |crystal structure comment= Face-centered cubic (fcc) | ||
+ | |crystal structure 2= | ||
+ | |crystal structure 2 prefix= | ||
+ | |crystal structure 2 ref= | ||
+ | |crystal structure 2 comment= | ||
+ | |speed of sound= | ||
+ | |speed of sound ref= | ||
+ | |speed of sound comment= | ||
+ | |speed of sound rod at 20= | ||
+ | |speed of sound rod at 20 ref= | ||
+ | |speed of sound rod at 20 comment= | ||
+ | |speed of sound rod at r.t.=2800 | ||
+ | |speed of sound rod at r.t. ref= | ||
+ | |speed of sound rod at r.t. comment= | ||
+ | |thermal expansion= | ||
+ | |thermal expansion ref= | ||
+ | |thermal expansion comment= | ||
+ | |thermal expansion at 25=8.8 | ||
+ | |thermal expansion at 25 ref= | ||
+ | |thermal expansion at 25 comment= | ||
+ | |thermal conductivity=71.6 | ||
+ | |thermal conductivity ref= | ||
+ | |thermal conductivity comment= | ||
+ | |thermal conductivity 2= | ||
+ | |thermal conductivity 2 ref= | ||
+ | |thermal conductivity 2 comment= | ||
+ | |thermal diffusivity= | ||
+ | |thermal diffusivity ref= | ||
+ | |thermal diffusivity comment= | ||
+ | |electrical resistivity= | ||
+ | |electrical resistivity unit prefix= | ||
+ | |electrical resistivity ref= | ||
+ | |electrical resistivity comment= | ||
+ | |electrical resistivity at 0= | ||
+ | |electrical resistivity at 0 ref= | ||
+ | |electrical resistivity at 0 comment= | ||
+ | |electrical resistivity at 20=1.05·10<sup>-7</sup> | ||
+ | |electrical resistivity at 20 ref= | ||
+ | |electrical resistivity at 20 comment= | ||
+ | |band gap= | ||
+ | |band gap ref= | ||
+ | |band gap comment= | ||
+ | |Curie point K= | ||
+ | |Curie point ref= | ||
+ | |Curie point comment= | ||
+ | |magnetic ordering=Paramagnetic | ||
+ | |magnetic ordering ref= | ||
+ | |magnetic ordering comment= | ||
+ | |tensile strength=125–240 | ||
+ | |tensile strength ref= | ||
+ | |tensile strength comment= | ||
+ | |Young's modulus=168 | ||
+ | |Young's modulus ref= | ||
+ | |Young's modulus comment= | ||
+ | |Shear modulus=61 | ||
+ | |Shear modulus ref= | ||
+ | |Shear modulus comment= | ||
+ | |Bulk modulus=230 | ||
+ | |Bulk modulus ref= | ||
+ | |Bulk modulus comment= | ||
+ | |Poisson ratio=0.38 | ||
+ | |Poisson ratio ref= | ||
+ | |Poisson ratio comment= | ||
+ | |Mohs hardness=3.5 | ||
+ | |Mohs hardness ref= | ||
+ | |Mohs hardness comment= | ||
+ | |Mohs hardness 2= | ||
+ | |Mohs hardness 2 ref= | ||
+ | |Mohs hardness 2 comment= | ||
+ | |Vickers hardness=400–550 | ||
+ | |Vickers hardness ref= | ||
+ | |Vickers hardness comment= | ||
+ | |Brinell hardness=300–500 | ||
+ | |Brinell hardness ref= | ||
+ | |Brinell hardness comment= | ||
+ | |CAS number=7440-06-4 | ||
+ | |CAS number ref= | ||
+ | |CAS number comment= | ||
+ | <!-- History --> | ||
+ | |naming= | ||
+ | |predicted by= | ||
+ | |prediction date ref= | ||
+ | |prediction date= | ||
+ | |discovered by= Antonio de Ulloa | ||
+ | |discovery date ref= | ||
+ | |discovery date=1748 | ||
+ | |first isolation by= | ||
+ | |first isolation date ref= | ||
+ | |first isolation date= | ||
+ | |discovery and first isolation by= | ||
+ | |named by= | ||
+ | |named date ref= | ||
+ | |named date= | ||
+ | |history comment label= | ||
+ | |history comment= | ||
+ | <!-- Isotopes --> | ||
+ | |isotopes= | ||
+ | |isotopes comment= | ||
+ | |engvar= | ||
+ | }} | ||
+ | '''Platinum''' is a chemical element with the chemical symbol '''Pt''' and the atomic number 78. It is a valuable and useful transition metal, part of the so called "[[platinum group metals]]". | ||
==Properties== | ==Properties== | ||
Line 5: | Line 277: | ||
Platinum is extremely resistant to organic and mineral acids. It will, however, dissolve extremely slowly in hot [[aqua regia]], to give [[chloroplatinic acid]]. | Platinum is extremely resistant to organic and mineral acids. It will, however, dissolve extremely slowly in hot [[aqua regia]], to give [[chloroplatinic acid]]. | ||
− | Pt + 4 HNO<sub>3</sub> + 6 HCl → H<sub>2</sub>PtCl<sub>6</sub> + 4 NO<sub>2</sub> + 4 H<sub>2</sub>O | + | :Pt + 4 HNO<sub>3</sub> + 6 HCl → H<sub>2</sub>PtCl<sub>6</sub> + 4 NO<sub>2</sub> + 4 H<sub>2</sub>O |
It will also be attacked by molten alkali and cyanides. | It will also be attacked by molten alkali and cyanides. | ||
Line 13: | Line 285: | ||
==Availability== | ==Availability== | ||
− | Although it can be bought from precious metal stores, platinum is also found in certain electronics and car exhaust catalysts. Electrodes are sometimes coated with platinum. Platinum can be obtained along with silver in small amounts from capacitors obtained through [[ | + | Although it can be bought from precious metal stores, platinum is also found in certain electronics and car exhaust catalysts. Electrodes are sometimes coated with platinum. Platinum can be obtained along with [[silver]] in small amounts from capacitors obtained through [[electronic recycling]]. |
Platinum bullion can be bought, which has the advantage of having purity expressed accurately. | Platinum bullion can be bought, which has the advantage of having purity expressed accurately. | ||
− | == | + | In Australia, platinum is classified as Category II precursor chemical and purchasing it requires and EUD.<ref>http://www.sciencemadness.org/talk/files.php?pid=452422&aid=51570</ref> |
+ | |||
+ | ==Isolation== | ||
Platinum can be extracted by dissolving it in aqua regia. The resulting chloroplatinic acid is converted to [[ammonium chloroplatinate]] by the addition of [[ammonium chloride]], that can be reduced to platinum metal by heating it, usually in a hydrogen atmosphere. This results in a platinum sponge. | Platinum can be extracted by dissolving it in aqua regia. The resulting chloroplatinic acid is converted to [[ammonium chloroplatinate]] by the addition of [[ammonium chloride]], that can be reduced to platinum metal by heating it, usually in a hydrogen atmosphere. This results in a platinum sponge. | ||
==Projects== | ==Projects== | ||
+ | *Make [[chloroplatinic acid]] | ||
+ | *Make platinum [[electrode]]s | ||
*Electrolysis | *Electrolysis | ||
+ | *Make chlorates and perchlorates | ||
− | ==Safety== | + | ==Handling== |
− | Being a noble metal, it is non-toxic, though some of its compounds should be handled with care. | + | ===Safety=== |
+ | Being a noble metal, it is non-toxic, though some of its compounds should be handled with care, as they're toxic. | ||
+ | |||
+ | ===Storage=== | ||
+ | No special storage is required for storing platinum, though platinum electrodes should be kept away from sulfur oxides which can "poison" it. | ||
+ | |||
+ | ===Disposal=== | ||
+ | It's best to recycle platinum, considering it's a rare and expensive metal. | ||
==References== | ==References== | ||
<references/> | <references/> | ||
===Relevant Sciencemadness threads=== | ===Relevant Sciencemadness threads=== | ||
− | + | *[https://www.sciencemadness.org/whisper/viewthread.php?tid=62306 Making Platinum Electrodes] | |
[[Category:Elements]] | [[Category:Elements]] | ||
[[Category:Metals]] | [[Category:Metals]] | ||
− | [[Category:Platinum | + | [[Category:Transition metals]] |
+ | [[Category:Platinum group]] | ||
+ | [[Category:Precious metals]] | ||
+ | [[Category:D-block]] | ||
+ | [[Category:Noble metals]] |
Latest revision as of 21:39, 25 January 2019
General properties | |||||
---|---|---|---|---|---|
Name, symbol | Platinum, Pt | ||||
Appearance | Silvery white metal | ||||
Platinum in the periodic table | |||||
| |||||
Atomic number | 78 | ||||
Standard atomic weight (Ar) | 195.084(9) | ||||
Group, block | , d-block | ||||
Period | period 6 | ||||
Electron configuration | [Xe] 4f14 5d9 6s1 | ||||
per shell | 2, 8, 18, 32, 17, 1 | ||||
Physical properties | |||||
Silvery-white | |||||
Phase | Solid | ||||
Melting point | 2041.4 K (1768.3 °C, 3214.9 °F) | ||||
Boiling point | 4098 K (3825 °C, 6917 °F) | ||||
Density near r.t. | 21.45 g/cm3 | ||||
when liquid, at | 19.77 g/cm3 | ||||
Heat of fusion | 22.17 kJ/mol | ||||
Heat of | 510 kJ/mol | ||||
Molar heat capacity | 25.86 J/(mol·K) | ||||
pressure | |||||
Atomic properties | |||||
Oxidation states | 6, 5, 4, 3, 2, 1, −1, −2, −3 (a mildly basic oxide) | ||||
Electronegativity | Pauling scale: 2.28 | ||||
energies |
1st: 870 kJ/mol 2nd: 1791 kJ/mol | ||||
Atomic radius | empirical: 139 pm | ||||
Covalent radius | 136±5 pm | ||||
Van der Waals radius | 175 pm | ||||
Miscellanea | |||||
Crystal structure | Face-centered cubic (fcc) | ||||
Speed of sound thin rod | 2800 m/s (at ) | ||||
Thermal expansion | 8.8 µm/(m·K) (at 25 °C) | ||||
Thermal conductivity | 71.6 W/(m·K) | ||||
Electrical resistivity | 1.05·10-7 Ω·m (at 20 °C) | ||||
Magnetic ordering | Paramagnetic | ||||
Tensile strength | 125–240 MPa | ||||
Young's modulus | 168 GPa | ||||
Shear modulus | 61 GPa | ||||
Bulk modulus | 230 GPa | ||||
Poisson ratio | 0.38 | ||||
Mohs hardness | 3.5 | ||||
Vickers hardness | 400–550 MPa | ||||
Brinell hardness | 300–500 MPa | ||||
CAS Registry Number | 7440-06-4 | ||||
History | |||||
Discovery | Antonio de Ulloa (1748) | ||||
Platinum is a chemical element with the chemical symbol Pt and the atomic number 78. It is a valuable and useful transition metal, part of the so called "platinum group metals".
Contents
Properties
Chemical
Platinum is extremely resistant to organic and mineral acids. It will, however, dissolve extremely slowly in hot aqua regia, to give chloroplatinic acid.
- Pt + 4 HNO3 + 6 HCl → H2PtCl6 + 4 NO2 + 4 H2O
It will also be attacked by molten alkali and cyanides.
Physical
Platinum is a lustrous, ductile, and malleable, silver-white metal. It is more ductile than gold, but less malleable.
Availability
Although it can be bought from precious metal stores, platinum is also found in certain electronics and car exhaust catalysts. Electrodes are sometimes coated with platinum. Platinum can be obtained along with silver in small amounts from capacitors obtained through electronic recycling.
Platinum bullion can be bought, which has the advantage of having purity expressed accurately.
In Australia, platinum is classified as Category II precursor chemical and purchasing it requires and EUD.[1]
Isolation
Platinum can be extracted by dissolving it in aqua regia. The resulting chloroplatinic acid is converted to ammonium chloroplatinate by the addition of ammonium chloride, that can be reduced to platinum metal by heating it, usually in a hydrogen atmosphere. This results in a platinum sponge.
Projects
- Make chloroplatinic acid
- Make platinum electrodes
- Electrolysis
- Make chlorates and perchlorates
Handling
Safety
Being a noble metal, it is non-toxic, though some of its compounds should be handled with care, as they're toxic.
Storage
No special storage is required for storing platinum, though platinum electrodes should be kept away from sulfur oxides which can "poison" it.
Disposal
It's best to recycle platinum, considering it's a rare and expensive metal.