Difference between revisions of "Platinum"

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|right=[[Gold]]
 
|right=[[Gold]]
 
|number=78
 
|number=78
|atomic mass=
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|atomic mass=195.084(9)
 
|atomic mass 2=
 
|atomic mass 2=
 
|atomic mass ref=
 
|atomic mass ref=
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|series comment=
 
|series comment=
 
|series color=
 
|series color=
|group=
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|group=10
 
|group ref=
 
|group ref=
 
|group comment=
 
|group comment=
|period=
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|period=6
 
|period ref=
 
|period ref=
 
|period comment=
 
|period comment=
|block=
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|block=d
 
|block ref=
 
|block ref=
 
|block comment=
 
|block comment=
|electron configuration=
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|electron configuration=[Xe] 4f<sup>14</sup> 5d<sup>9</sup> 6s<sup>1</sup>
 
|electron configuration ref=
 
|electron configuration ref=
 
|electron configuration comment=
 
|electron configuration comment=
|electrons per shell=
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|electrons per shell=2, 8, 18, 32, 17, 1
 
|electrons per shell ref=
 
|electrons per shell ref=
 
|electrons per shell comment=
 
|electrons per shell comment=
 
<!-- Physical properties -->
 
<!-- Physical properties -->
 
|physical properties comment=
 
|physical properties comment=
|color=
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|color=Silvery-white
|phase=
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|phase=Solid
 
|phase ref=
 
|phase ref=
 
|phase comment=
 
|phase comment=
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|critical point ref=
 
|critical point ref=
 
|critical point comment=
 
|critical point comment=
|heat fusion=
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|heat fusion=22.17
 
|heat fusion ref=
 
|heat fusion ref=
 
|heat fusion comment=
 
|heat fusion comment=
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|heat fusion 2 ref=
 
|heat fusion 2 ref=
 
|heat fusion 2 comment=
 
|heat fusion 2 comment=
|heat vaporization=
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|heat vaporization=510
 
|heat vaporization ref=
 
|heat vaporization ref=
 
|heat vaporization comment=
 
|heat vaporization comment=
|heat capacity=
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|heat capacity=25.86
 
|heat capacity ref=
 
|heat capacity ref=
 
|heat capacity comment=
 
|heat capacity comment=
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|heat capacity 2 ref=
 
|heat capacity 2 ref=
 
|heat capacity 2 comment=
 
|heat capacity 2 comment=
|vapor pressure 1=
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|vapor pressure 1=2330
|vapor pressure 10=
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|vapor pressure 10=(2550)
|vapor pressure 100=
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|vapor pressure 100=2815
|vapor pressure 1 k=
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|vapor pressure 1 k=3143
|vapor pressure 10 k=
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|vapor pressure 10 k=3556
|vapor pressure 100 k=
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|vapor pressure 100 k=4094
 
|vapor pressure ref=
 
|vapor pressure ref=
 
|vapor pressure comment=
 
|vapor pressure comment=
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<!-- Atomic properties -->
 
<!-- Atomic properties -->
 
|atomic properties comment=
 
|atomic properties comment=
|oxidation states=
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|oxidation states=6, 5, '''4''', 3, '''2''', 1, −1, −2, −3 ​
 
|oxidation states ref=
 
|oxidation states ref=
|oxidation states comment=
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|oxidation states comment=(a mildly basic oxide)
|electronegativity=
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|electronegativity=2.28
 
|electronegativity ref=
 
|electronegativity ref=
 
|electronegativity comment=
 
|electronegativity comment=
|ionization energy 1=
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|ionization energy 1=870
 
|ionization energy 1 ref=
 
|ionization energy 1 ref=
 
|ionization energy 1 comment=
 
|ionization energy 1 comment=
|ionization energy 2=
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|ionization energy 2=1791
 
|ionization energy 2 ref=
 
|ionization energy 2 ref=
 
|ionization energy 2 comment=
 
|ionization energy 2 comment=
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|ionization energy ref=
 
|ionization energy ref=
 
|ionization energy comment=
 
|ionization energy comment=
|atomic radius=
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|atomic radius=139
 
|atomic radius ref=
 
|atomic radius ref=
 
|atomic radius comment=
 
|atomic radius comment=
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|atomic radius calculated ref=
 
|atomic radius calculated ref=
 
|atomic radius calculated comment=
 
|atomic radius calculated comment=
|covalent radius=
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|covalent radius=136±5
 
|covalent radius ref=
 
|covalent radius ref=
 
|covalent radius comment=
 
|covalent radius comment=
|Van der Waals radius=
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|Van der Waals radius=175
 
|Van der Waals radius ref=
 
|Van der Waals radius ref=
 
|Van der Waals radius comment=
 
|Van der Waals radius comment=
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|crystal structure prefix=
 
|crystal structure prefix=
 
|crystal structure ref=
 
|crystal structure ref=
|crystal structure comment=
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|crystal structure comment= Face-centered cubic (fcc)
 
|crystal structure 2=
 
|crystal structure 2=
 
|crystal structure 2 prefix=
 
|crystal structure 2 prefix=
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|speed of sound rod at 20 ref=
 
|speed of sound rod at 20 ref=
 
|speed of sound rod at 20 comment=
 
|speed of sound rod at 20 comment=
|speed of sound rod at r.t.=
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|speed of sound rod at r.t.=2800
 
|speed of sound rod at r.t. ref=
 
|speed of sound rod at r.t. ref=
 
|speed of sound rod at r.t. comment=
 
|speed of sound rod at r.t. comment=
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|thermal expansion ref=
 
|thermal expansion ref=
 
|thermal expansion comment=
 
|thermal expansion comment=
|thermal expansion at 25=
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|thermal expansion at 25=8.8
 
|thermal expansion at 25 ref=
 
|thermal expansion at 25 ref=
 
|thermal expansion at 25 comment=
 
|thermal expansion at 25 comment=
|thermal conductivity=
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|thermal conductivity=71.6
 
|thermal conductivity ref=
 
|thermal conductivity ref=
 
|thermal conductivity comment=
 
|thermal conductivity comment=
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|electrical resistivity at 0 ref=
 
|electrical resistivity at 0 ref=
 
|electrical resistivity at 0 comment=
 
|electrical resistivity at 0 comment=
|electrical resistivity at 20=
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|electrical resistivity at 20=1.05·10<sup>-7</sup>
 
|electrical resistivity at 20 ref=
 
|electrical resistivity at 20 ref=
 
|electrical resistivity at 20 comment=
 
|electrical resistivity at 20 comment=
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|Curie point ref=
 
|Curie point ref=
 
|Curie point comment=
 
|Curie point comment=
|magnetic ordering=
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|magnetic ordering=Paramagnetic
 
|magnetic ordering ref=
 
|magnetic ordering ref=
 
|magnetic ordering comment=
 
|magnetic ordering comment=
|tensile strength=
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|tensile strength=125–240
 
|tensile strength ref=
 
|tensile strength ref=
 
|tensile strength comment=
 
|tensile strength comment=
|Young's modulus=
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|Young's modulus=168
 
|Young's modulus ref=
 
|Young's modulus ref=
 
|Young's modulus comment=
 
|Young's modulus comment=
|Shear modulus=
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|Shear modulus=61
 
|Shear modulus ref=
 
|Shear modulus ref=
 
|Shear modulus comment=
 
|Shear modulus comment=
|Bulk modulus=
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|Bulk modulus=230
 
|Bulk modulus ref=
 
|Bulk modulus ref=
 
|Bulk modulus comment=
 
|Bulk modulus comment=
|Poisson ratio=
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|Poisson ratio=0.38
 
|Poisson ratio ref=
 
|Poisson ratio ref=
 
|Poisson ratio comment=
 
|Poisson ratio comment=
|Mohs hardness=
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|Mohs hardness=3.5
 
|Mohs hardness ref=
 
|Mohs hardness ref=
 
|Mohs hardness comment=
 
|Mohs hardness comment=
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|Mohs hardness 2 ref=
 
|Mohs hardness 2 ref=
 
|Mohs hardness 2 comment=
 
|Mohs hardness 2 comment=
|Vickers hardness=
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|Vickers hardness=400–550
 
|Vickers hardness ref=
 
|Vickers hardness ref=
 
|Vickers hardness comment=
 
|Vickers hardness comment=
|Brinell hardness=
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|Brinell hardness=300–500
 
|Brinell hardness ref=
 
|Brinell hardness ref=
 
|Brinell hardness comment=
 
|Brinell hardness comment=
|CAS number=
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|CAS number=7440-06-4
 
|CAS number ref=
 
|CAS number ref=
 
|CAS number comment=
 
|CAS number comment=
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|prediction date ref=
 
|prediction date ref=
 
|prediction date=
 
|prediction date=
|discovered by=
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|discovered by= Antonio de Ulloa
 
|discovery date ref=
 
|discovery date ref=
|discovery date=
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|discovery date=1748
 
|first isolation by=
 
|first isolation by=
 
|first isolation date ref=
 
|first isolation date ref=
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==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 [[electronic recycling]].
+
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.
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==Projects==
 
==Projects==
*Make [[hexachloroplatinic acid]]
+
*Make [[chloroplatinic acid]]
*Make platinum electrodes
+
*Make platinum [[electrode]]s
 
*Electrolysis
 
*Electrolysis
 
*Make chlorates and perchlorates
 
*Make chlorates and perchlorates
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==Handling==
 
==Handling==
 
===Safety===
 
===Safety===
Being a noble metal, it is non-toxic, though some of its compounds should be handled with care.
+
Being a noble metal, it is non-toxic, though some of its compounds should be handled with care, as they're toxic.
  
 
===Storage===
 
===Storage===

Latest revision as of 21:39, 25 January 2019

Platinum,  78Pt
General properties
Name, symbol Platinum, Pt
Appearance Silvery white metal
Platinum in the periodic table
Pd

Pt

Ds
IridiumPlatinumGold
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)
· references

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

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

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.

References

  1. http://www.sciencemadness.org/talk/files.php?pid=452422&aid=51570

Relevant Sciencemadness threads