Symbol
Au
  
Nb
  
Period Number
6
  
5
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
Fm_ 3m
  
Im_ 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.
  
- Niobium metal was used to get called Columbium in past.
- Niobium metal found freely in nature (abundance).
  
Sources
Earth's crust, Mining, Ores of metals
  
By-product of Tin Extraction, Found in Minerals, Mining, Ores of Minerals
  
History
  
  
Who Discovered
Unknown
  
Charles Hatchett
  
Discovery
Before 6000 BCE
  
In 1801
  
Abundance
  
  
Abundance In Sun
~0.0000001 %
  
26
~0.0000004 %
  
23
Abundance In Earth's Crust
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.
  
- Niobium alloys are used in jet engines and rockets and spacecraft, beams and girders for buildings and oil and gas pipelines.
- It is used superconducting magnets in particles accelerators, NMR and MRI equipment.
  
Industrial Uses
Chemical Industry, Clothing Industry, Electrical Industry, Electronic Industry
  
Aerospace Industry, Ammunition 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
  
Low Toxic
  
Present in Human Body
Yes
  
Yes
  
In Blood
0.00 Blood/mg dm-3
  
35
0.01 Blood/mg dm-3
  
25
In Bone
0.02 p.p.m.
  
30
0.07 p.p.m.
  
25
Melting Point
1,064.43 °C
  
99+
Boiling Point
2,807.00 °C
  
36
2,468.00 °C
  
99+
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gold
  
Gray
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Brinell Hardness
194.00 MPa
  
99+
Speed of Sound
2,030.00 m/s
  
99+
3,480.00 m/s
  
21
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
Au
  
Nb
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
890.10 kJ/mol
  
8
652.10 kJ/mol
  
99+
2nd Energy Level
1,980.00 kJ/mol
  
12
1,380.00 kJ/mol
  
99+
3rd Energy Level
Not Available
  
2,416.00 kJ/mol
  
99+
4th Energy Level
Not Available
  
3,700.00 kJ/mol
  
99+
5th Energy Level
Not Available
  
4,877.00 kJ/mol
  
36
6th Energy Level
Not Available
  
9,847.00 kJ/mol
  
11
7th Energy level
Not Available
  
12,100.00 kJ/mol
  
14
Electrochemical Equivalent
2.45 g/amp-hr
  
21
0.69 g/amp-hr
  
99+
Other Chemical Properties
Chemical Stability, Ionization, Solubility
  
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Xe] 4f14 5d10 6s1
  
[Kr] 4d4 5s1
  
Crystal Structure
Face Centered Cubic (FCC)
  
Body Centered Cubic (BCC)
  
Crystal Lattice
FCC-Crystal-Structure-of-Gold.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
10.20 cm3/mol
  
99+
10.87 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
43.40 (-eV)
  
99+
104.00 (-eV)
  
8
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
8.57 g/cm3
  
99+
Density When Liquid (at m.p.)
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable
  
Ductile, Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Diamagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
152.00 nΩ·m
  
23
Electrical Conductivity
0.45 106/cm Ω
  
3
0.07 106/cm Ω
  
28
Electron Affinity
222.80 kJ/mol
  
1
86.10 kJ/mol
  
12
Specific Heat
0.13 J/(kg K)
  
39
0.26 J/(kg K)
  
20
Molar Heat Capacity
25.42 J/mol·K
  
40
24.60 J/mol·K
  
99+
Thermal Conductivity
318.00 W/m·K
  
3
53.70 W/m·K
  
29
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
14.20 µm/(m·K)
  
26
7.30 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
324.40 kJ/mol
  
27
696.60 kJ/mol
  
4
Enthalpy of Fusion
12.55 kJ/mol
  
27
27.20 kJ/mol
  
6
Enthalpy of Atomization
364.00 kJ/mol
  
25
745.00 kJ/mol
  
4
Standard Molar Entropy
47.40 J/mol.K
  
32
36.40 J/mol.K
  
99+