PLATINUM SPECIFICATIONS

Pronunciation/ˈplætɪnəm/​(PLAT-ə-nəm)

 

General properties

Appearance: Silvery white
Standard atomic weight (Ar, standard) 195.084 (9)[1]

iridium ← platinum → gold

Atomic number (Z)78
Group: group 10
Period: period 6
Element category: transition metal
Block: d-block
Electron configuration: [Xe] 4f14 5d9 6s1

Electrons per shell: 2, 8, 18, 32, 17, 1

 

Physical Properties

Phase at STP solid
Melting point 2041.4 K ​(1768.3°C, ​3214.9°F)
Boiling point 4098 K ​(3825°C, ​6917°F)
Boiling point 4098 K ​(3825°C, ​6917°F)
Density (near r.t.)21.45 g/cm3 when liquid (at m.p.)19.77 g/cm3
Heat of fusion 22.17 kJ/mol
Heat of vaporization 510 kJ/mol
Molar heat capacity 25.86 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 6, 5, 4, 3, 2, 1, −1, −2, −3 ​(a mildly basic oxide)
Electro negativity Pauling scale: 2.28

 

Ionization Energies:

1st: 870 kJ/mol
2nd: 1791 kJ/mol

Atomic Radius Empirical: 139pm
Covalent Radius: 136±5pm
Van der Waals Radius 175pm

 

Other Properties:

Crystal structure​ face-centered cubic (fcc)

Speed of sound thin rod 2800 m/s (at r.t.)
Thermal expansion 8.8 µm/(m·K) (at 25°C)
Thermal conductivity 71.6 W/(m·K)
Electrical resistivity 105 nΩ·m (at 20°C)
Magnetic ordering paramagnetic
Magnetic susceptibility +201.9·10−6 cm3/mol (290 K)[2]
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 Number 7440-06-4
History: Discovered by Antonio de Ulloa (1735)

 

Main isotopes of platinum

 

Iso­-tope Abun­dance Half-life (t 1/2) Decay mode Product
190Pt 0.012% 6.5×1011 y α 1860s
192Pt 0.782% stable
193Pt syn 50 y ε 193Ir
194Pt 32.864% stable
195Pt 33.775% stable
196Pt 25.211% stable
198Pt 7.356% stable