Symbol
Th
  
Ir
  
Period Number
7
  
6
  
Block
f block
  
d block
  
Element Family
Actinide
  
Transition Metal
  
Space Group Name
P63/mmc
  
Fm_ 3m
  
Interesting Facts
- Thorium metal is used as an alternate option over Uranium for nuclear fuel.
- Thorium metals appearance (silvery white, soft) is somewhat similar to Lead metal.
  
- Iridium element occurs as natural alloys of Platinum and Osmium.
- Iridium element is known as the most corrosion resistance metal .
  
Sources
Found in Minerals, Mining
  
Found in Minerals, Mining, Ores of Minerals
  
History
  
  
Who Discovered
Jöns Jakob Berzelius
  
Smithson Tennant
  
Discovery
In 1829
  
In 1803
  
Abundance
  
  
Abundance In Sun
~0.0000002 %
  
25
Abundance In Earth's Crust
Abundance In Oceans
Not Available
  
Uses & Benefits
- Thorium metal is used as an allying agent for Magnesium, It imparts greater strength and resistance to temperature.
-
compound of this metal Thorium oxide is used as an industrial catalyst.
  
- Iridium has an anti corrosion properties and it is used in special alloy with Osmium metal and that alloy is used in pen tips and compass bearings.
  
Industrial Uses
Aerospace Industry, Automobile Industry, Chemical Industry, Electrical Industry, Electronic Industry
  
Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
Dentistry, Surgical Instruments Manufacturing
  
NA
  
Other Uses
Alloys, Jewellery, Sculptures, Statues
  
Alloys
  
Biological Properties
  
  
Toxicity
Non Toxic
  
Toxic
  
Present in Human Body
Yes
  
Yes
  
In Blood
0.00 Blood/mg dm-3
  
33
Not Available
  
In Bone
0.02 p.p.m.
  
29
Not Available
  
Melting Point
1,750.00 °C
  
17
Boiling Point
4,527.00 °C
  
10
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silver
  
Silvery White
  
Luster
NA
  
Metallic
  
Hardness
  
  
Brinell Hardness
1,670.00 MPa
  
5
Vickers Hardness
1,760.00 MPa
  
3
Speed of Sound
2,490.00 m/s
  
36
4,825.00 m/s
  
13
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
Th
  
Ir
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Allred Rochow Electronegativity
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
587.00 kJ/mol
  
99+
880.00 kJ/mol
  
9
2nd Energy Level
1,110.00 kJ/mol
  
99+
1,600.00 kJ/mol
  
35
3rd Energy Level
1,978.00 kJ/mol
  
99+
Not Available
  
4th Energy Level
2,780.00 kJ/mol
  
99+
Not Available
  
Electrochemical Equivalent
2.16 g/amp-hr
  
24
1.14 g/amp-hr
  
99+
Other Chemical Properties
Corrosion, Ionization, Radioactive Isotopes, Radioactivity
  
Flammable, Ionization, Radioactive Isotopes, Radioactivity
  
Electron Configuration
[Rn] 6d2 7s2
  
[Xe] 4f14 5d7 6s2
  
Crystal Structure
Face Centered Cubic (FCC)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
FCC-Crystal-Structure-of-Thorium.jpg#100
  
FCC-Crystal-Structure-of-Iridium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
19.90 cm3/mol
  
20
9.53 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
59.30 (-eV)
  
23
140.00 (-eV)
  
5
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
11.72 g/cm3
  
32
22.56 g/cm3
  
10
Density When Liquid (at m.p.)
Not Available
  
Tensile Strength
Not Available
  
2,000.00 MPa
  
2
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Superconductor
  
Conductor
  
Resistivity
157.00 nΩ·m
  
22
47.10 nΩ·m
  
99+
Electrical Conductivity
0.07 106/cm Ω
  
31
0.19 106/cm Ω
  
10
Electron Affinity
Not Available
  
151.00 kJ/mol
  
4
Specific Heat
0.12 J/(kg K)
  
40
0.13 J/(kg K)
  
39
Molar Heat Capacity
26.23 J/mol·K
  
30
25.10 J/mol·K
  
99+
Thermal Conductivity
54.00 W/m·K
  
28
147.00 W/m·K
  
10
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
11.00 µm/(m·K)
  
36
6.40 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
429.00 kJ/mol
  
15
799.10 kJ/mol
  
1
Enthalpy of Fusion
15.48 kJ/mol
  
19
35.23 kJ/mol
  
1
Enthalpy of Atomization
468.60 kJ/mol
  
15
837.00 kJ/mol
  
1
Standard Molar Entropy
27.30 J/mol.K
  
99+
35.50 J/mol.K
  
99+