Symbol
Au
  
Ir
  
Period Number
6
  
6
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
Fm_ 3m
  
Fm_ 3m
  
Interesting Facts
- It is found in copper ores and from the crust of the earth.
- It is the most malleable and ductile metal.
- Gold alloys are used in Dentistry as fillings, crowning, clips, etc. It is also used as an artificial limb joints.
  
- Iridium element occurs as natural alloys of Platinum and Osmium.
- Iridium element is known as the most corrosion resistance metal .
  
Sources
Earth's crust, Mining, Ores of metals
  
Found in Minerals, Mining, Ores of Minerals
  
History
  
  
Who Discovered
Unknown
  
Smithson Tennant
  
Discovery
Before 6000 BCE
  
In 1803
  
Abundance
  
  
Abundance In Sun
~0.0000001 %
  
26
~0.0000002 %
  
25
Abundance In Earth's Crust
Abundance In Oceans
Not Available
  
Abundance In Humans
Not Available
  
Uses & Benefits
- Gold metal is mainly used for Jewelry, bullion, coinage, etc.
- It is used in the art, decoration, ornaments, etc. It is also used for electroplating process.
  
- 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
Chemical Industry, Clothing Industry, Electrical Industry, Electronic Industry
  
Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
Dentistry, Pharmaceutical Industry
  
NA
  
Other Uses
Alloys, Bullion, Coinage, Jewellery, Sculptures, Statues
  
Alloys
  
Biological Properties
  
  
Toxicity
Non Toxic
  
Toxic
  
Present in Human Body
Yes
  
Yes
  
In Blood
0.00 Blood/mg dm-3
  
35
Not Available
  
In Bone
0.02 p.p.m.
  
30
Not Available
  
Melting Point
1,064.43 °C
  
99+
Boiling Point
2,807.00 °C
  
36
4,527.00 °C
  
10
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gold
  
Silvery White
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Brinell Hardness
194.00 MPa
  
99+
1,670.00 MPa
  
5
Vickers Hardness
1,760.00 MPa
  
3
Speed of Sound
2,030.00 m/s
  
99+
4,825.00 m/s
  
13
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Au
  
Ir
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
890.10 kJ/mol
  
8
880.00 kJ/mol
  
9
2nd Energy Level
1,980.00 kJ/mol
  
12
1,600.00 kJ/mol
  
35
Electrochemical Equivalent
2.45 g/amp-hr
  
21
1.14 g/amp-hr
  
99+
Other Chemical Properties
Chemical Stability, Ionization, Solubility
  
Flammable, Ionization, Radioactive Isotopes, Radioactivity
  
Electron Configuration
[Xe] 4f14 5d10 6s1
  
[Xe] 4f14 5d7 6s2
  
Crystal Structure
Face Centered Cubic (FCC)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
FCC-Crystal-Structure-of-Gold.jpg#100
  
FCC-Crystal-Structure-of-Iridium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
10.20 cm3/mol
  
99+
9.53 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
43.40 (-eV)
  
99+
140.00 (-eV)
  
5
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Density
  
  
Density At Room Temperature
19.30 g/cm3
  
15
22.56 g/cm3
  
10
Density When Liquid (at m.p.)
Tensile Strength
2,000.00 MPa
  
2
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Diamagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
47.10 nΩ·m
  
99+
Electrical Conductivity
0.45 106/cm Ω
  
3
0.19 106/cm Ω
  
10
Electron Affinity
222.80 kJ/mol
  
1
151.00 kJ/mol
  
4
Specific Heat
0.13 J/(kg K)
  
39
0.13 J/(kg K)
  
39
Molar Heat Capacity
25.42 J/mol·K
  
40
25.10 J/mol·K
  
99+
Thermal Conductivity
318.00 W/m·K
  
3
147.00 W/m·K
  
10
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
14.20 µm/(m·K)
  
26
6.40 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
324.40 kJ/mol
  
27
799.10 kJ/mol
  
1
Enthalpy of Fusion
12.55 kJ/mol
  
27
35.23 kJ/mol
  
1
Enthalpy of Atomization
364.00 kJ/mol
  
25
837.00 kJ/mol
  
1
Standard Molar Entropy
47.40 J/mol.K
  
32
35.50 J/mol.K
  
99+