Platinum

Platinum, 78Pt
Platinum
Pronunciation/ˈplætənəm/ (PLAT-ən-əm)
Appearancesilvery white
Standard atomic weight Ar°(Pt)
195.084(9)[1]
Platinum in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Pd

Pt

Ds
iridiumplatinumgold
Atomic number (Z)78
Groupgroup 10
Periodperiod 6
Block  d-block
Electron configuration[Xe] 4f14 5d9 6s1
Electrons per shell2, 8, 18, 32, 17, 1
Physical properties
Phase at STPsolid
Melting point2041.4 K ​(1768.3 °C, ​3214.9 °F)
Boiling point4098 K ​(3825 °C, ​6917 °F)
Density (near r.t.)21.45 g/cm3
when liquid (at m.p.)19.77 g/cm3
Heat of fusion22.17 kJ/mol
Heat of vaporization510 kJ/mol
Molar heat capacity25.86 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2330 (2550) 2815 3143 3556 4094
Atomic properties
Oxidation states−3, −2, −1, 0, +1, +2, +3, +4, +5, +6 (a mildly basic oxide)
ElectronegativityPauling scale: 2.28
Ionization energies
  • 1st: 870 kJ/mol
  • 2nd: 1791 kJ/mol
Atomic radiusempirical: 139 pm
Covalent radius136±5 pm
Van der Waals radius175 pm
Spectral lines of platinum
Other properties
Natural occurrenceprimordial
Crystal structureface-centered cubic (fcc)
Speed of sound thin rod2800 m/s (at r.t.)
Thermal expansion8.8 µm/(m⋅K) (at 25 °C)
Thermal conductivity71.6 W/(m⋅K)
Electrical resistivity105 nΩ⋅m (at 20 °C)
Magnetic orderingparamagnetic
Molar magnetic susceptibility+201.9 × 10−6 cm3/mol (290 K)[2]
Tensile strength125–240 MPa
Young's modulus168 GPa
Shear modulus61 GPa
Bulk modulus230 GPa
Poisson ratio0.38
Mohs hardness3.5
Vickers hardness400–550 MPa
Brinell hardness300–500 MPa
CAS Number7440-06-4
History
DiscoveryAntonio de Ulloa (1735)
Isotopes of platinum
Main isotopes[3] Decay
abun­dance half-life (t1/2) mode pro­duct
190Pt 0.0120% 4.83×1011 y α 186Os
192Pt 0.782% stable
193Pt synth 50 y ε 193Ir
194Pt 32.9% stable
195Pt 33.8% stable
196Pt 25.2% stable
198Pt 7.36% stable

Platinum is a chemical element. It has symbol Pt and atomic number 78. Platinum is a soft, heavy, white metal. It is a precious metal and a transition metal. Its name comes from the Spanish word platina meaning "little silver".[4][5]

Platinum is part of the platinum group of elements. It is on group 10 in the periodic table of elements. Its atoms have an atomic weight of 195 atomic mass units. It has 6 isotopes that is found in nature. Platinum can be found in some nickel and copper ores. 90% of platinum is found in the Ural Mountains, Colombia, the Sudbury basin of Canada, and a large reserve in South Africa.[6]: 779 

In the past, it was worth more than gold. Since the late 2010s, gold cost more. The element is hard to find in the Earth's crust. It has an average abundance of about 5 μg/kg.[6] Since it is so rare, only a few hundred tonnes of Platinum are made every year.

Platinum is very dense; almost twice as dense as lead. It is malleable and ductile. This means it can be made thin sheets and it can be pulled into wire. Platinum is very stable. Acids do not change platinum.


Platinum has many uses. The most common use of Platinum is in a vehicle's catalytic converter. It is also used in laboratory equipment, electrical contacts and electrodes, platinum resistance thermometers, dentistry equipment, and jewelry. Platinum is also used in the glass industry.[7] There, it is used to change molten glass. Elemental platinum is not found to be dangerous to human health. Compounds that have platinum, such as cisplatin, oxaliplatin and carboplatin, are used in chemotherapy against some types of cancer.[8]

Platinum group

References

  1. "Standard Atomic Weights: Platinum". CIAAW. 2005.
  2. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
  3. Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  4. "platinum (Pt)". Encyclopædia Britannica. Encyclopædia Britannica Inc. 2012. Archived from the original on 5 April 2012. Retrieved 24 April 2012.
  5. Harper, Douglas. "platinum". Online Etymology Dictionary.
  6. 6.0 6.1 Sicius, Hermann (2024). Handbook of the Chemical Elements. Berlin, Heidelberg: Springer Berlin Heidelberg. doi:10.1007/978-3-662-68921-9. ISBN 978-3-662-68920-2.
  7. Preston, Eric (1960). "Platinum in the Glass Industry". Platinum Metals Review. 4: 2–9. doi:10.1595/003214060X4129.
  8. Wheate, N. J.; Walker, S.; Craig, G. E.; Oun, R. (2010). "The status of platinum anticancer drugs in the clinic and in clinical trials" (PDF). Dalton Transactions. 39 (35): 8113–27. doi:10.1039/C0DT00292E. hdl:2123/14271. PMID 20593091.

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