Symbol
Hf
  
Pt
  
Period Number
6
  
6
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
P63/mmc
  
Fm_ 3m
  
Interesting Facts
- Hafnium metal is highly reactive, hence not found free in nature.
- Hafnium metal as predicated after Mendeleev finished his periodic table.
  
- Platinum is the rarest metal from the Precious metal categories..
- Commercially Platinum is produced as a byproduct in ores of nickel.
  
Sources
By-product Zirconium Refining
  
Mining, Ores of metals, Ores of Minerals
  
History
  
  
Who Discovered
Dirk Coster and George de Hevesy
  
Antonio de Ulloa
  
Discovery
In 1922
  
In 1735
  
Abundance
  
  
Abundance In Sun
~0.0000001 %
  
26
~0.0000009 %
  
19
Abundance In Earth's Crust
Abundance In Oceans
Not Available
  
Uses & Benefits
- It has an ability to absorb neutrons and hence it is used to make control rods in nuclear submarines. And this metal is also used in Plasma welding torches.
-
It alloys with iron, titanium and niobium are very useful.
  
- Platinum metal is mainly used in jewellery.
-
Platinum is used as an industrial catalyst in production of nitric acid, silicone and benzene.
  
Industrial Uses
Ammunition Industry
  
Aerospace Industry, Chemical Industry
  
Medical Uses
NA
  
Dentistry, Pharmaceutical Industry, Surgical Instruments Manufacturing
  
Other Uses
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes
  
Alloys, Bullion, Coinage, Jewellery, Sculptures, Statues
  
Biological Properties
  
  
Toxicity
Toxic
  
Non Toxic
  
Present in Human Body
No
  
No
  
Melting Point
2,150.00 °C
  
10
1,772.00 °C
  
16
Boiling Point
3,827.00 °C
  
15
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Silvery White
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Brinell Hardness
1,450.00 MPa
  
6
Vickers Hardness
1,520.00 MPa
  
5
Speed of Sound
3,010.00 m/s
  
27
2,800.00 m/s
  
29
Optical Properties
  
  
Reflectivity
Not Available
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Hf
  
Pt
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Allred Rochow Electronegativity
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
658.50 kJ/mol
  
40
870.00 kJ/mol
  
10
2nd Energy Level
1,440.00 kJ/mol
  
99+
1,791.00 kJ/mol
  
21
3rd Energy Level
2,250.00 kJ/mol
  
99+
Not Available
  
4th Energy Level
3,216.00 kJ/mol
  
99+
Not Available
  
Electrochemical Equivalent
1.66 g/amp-hr
  
99+
1.82 g/amp-hr
  
35
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Chemical Stability, Anti Corrosion, Ionization
  
Electron Configuration
[Xe] 4f14 5d2 6s2
  
[Xe] 4f14 5d9 6s1
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
FCC-Crystal-Structure-of-Platinum.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
13.60 cm3/mol
  
38
9.09 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
81.00 (-eV)
  
16
392.42 (-eV)
  
1
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Density
  
  
Density At Room Temperature
13.31 g/cm3
  
26
21.45 g/cm3
  
11
Density When Liquid (at m.p.)
12.00 g/cm3
  
12
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable
  
Ductile, Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Permeability
Not Available
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
331.00 nΩ·m
  
14
105.00 nΩ·m
  
30
Electrical Conductivity
0.03 106/cm Ω
  
39
0.10 106/cm Ω
  
21
Electron Affinity
0.00 kJ/mol
  
40
205.30 kJ/mol
  
2
Specific Heat
0.14 J/(kg K)
  
37
0.13 J/(kg K)
  
39
Molar Heat Capacity
25.73 J/mol·K
  
36
25.86 J/mol·K
  
35
Thermal Conductivity
23.00 W/m·K
  
99+
71.60 W/m·K
  
24
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
5.90 µm/(m·K)
  
99+
8.80 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
661.10 kJ/mol
  
5
510.50 kJ/mol
  
11
Enthalpy of Fusion
25.10 kJ/mol
  
8
19.70 kJ/mol
  
12
Enthalpy of Atomization
703.00 kJ/mol
  
5
565.00 kJ/mol
  
11
Standard Molar Entropy
43.60 J/mol.K
  
34
41.60 J/mol.K
  
36