Symbol
Hg
  
Rh
  
Period Number
6
  
5
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
R_ 3m
  
Fm_ 3m
  
Interesting Facts
- At room temperature mercury is found in a liquid state.
- A coin of pound or rupees floats in mercury.
- Because of its low melting point and boiling point it is used in thermometers.
  
- Rhodium is the rarest element out of all non-radioactive metals on the earth .
- Rhodium is one of the most durable and hard metal, which also have high reflectance.
  
Sources
Mining, Ores of Minerals
  
Earth's crust, Found As a By-product, Found in Minerals, Mining
  
History
  
  
Who Discovered
Ancient Chinese and Indians
  
William Hyde Wollaston
  
Discovery
Before 2000 BCE
  
In 1804
  
Abundance
  
  
Abundance In Universe
Not Available
  
Abundance In Sun
~-9999 %
  
~0.0000002 %
  
25
Abundance In Meteorites
Not Available
  
Abundance In Earth's Crust
Uses & Benefits
- It is a liquid metal at room temperature, but it is a toxic heavy metal and hence many uses of mercury are under review or phased out.
- It is manly used as a catalysts in chemical industry.
  
- Rhodium metal is mainly used in catalytic converters for cars as it reduces nitrogen oxides in exhaust gases.
- It is used as an industrial catalyst for nitric acid, acetic acid, hydrogenation reaction, etc.
  
Industrial Uses
Electrical Industry, Electronic Industry
  
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
Dentistry
  
NA
  
Other Uses
Alloys, Mirror Manufacturing, Pharmaceutical Industry
  
Alloys
  
Biological Properties
  
  
Toxicity
Highly Toxic
  
NA
  
Present in Human Body
Yes
  
No
  
In Blood
0.01 Blood/mg dm-3
  
23
Not Available
  
In Bone
0.45 p.p.m.
  
19
Not Available
  
Melting Point
Not Available
  
1,966.00 °C
  
12
Boiling Point
3,727.00 °C
  
17
Appearance
  
  
Physical State
Liquid
  
Solid
  
Color
Silver
  
Silvery White
  
Luster
NA
  
Metallic
  
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
Not Available
  
Vickers Hardness
Not Available
  
1,100.00 MPa
  
9
Speed of Sound
1,451.40 m/s
  
99+
4,700.00 m/s
  
15
Optical Properties
  
  
Refractive Index
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
Hg
  
Rh
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
1,007.10 kJ/mol
  
4
719.70 kJ/mol
  
29
2nd Energy Level
1,810.00 kJ/mol
  
20
1,740.00 kJ/mol
  
26
3rd Energy Level
3,300.00 kJ/mol
  
20
2,997.00 kJ/mol
  
27
Electrochemical Equivalent
3.74 g/amp-hr
  
10
1.28 g/amp-hr
  
99+
Other Chemical Properties
Flammability, Ionization, Solubility
  
Anti Corrosion, Ionization, Radioactive Isotopes
  
Electron Configuration
[Xe] 4f14 5d10 6s2
  
[Kr] 4d8 5s1
  
Crystal Structure
Rhombohedral (RHO)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
RHO-Crystal-Structure-of-Mercury.jpg#100
  
FCC-Crystal-Structure-of-Rhodium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
102.91 amu
  
99+
Atomic Volume
14.82 cm3/mol
  
35
8.30 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
28.20 (-eV)
  
99+
64.00 (-eV)
  
22
Lattice Angles
NA
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
13.53 g/cm
3
  
24
12.41 g/cm
3
  
28
Density When Liquid (at m.p.)
Not Available
  
10.70 g/cm3
  
14
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Shear Modulus
Not Available
  
Bulk Modulus
Not Available
  
Young's Modulus
Not Available
  
Poisson Ratio
Not Available
  
Other Mechanical Properties
NA
  
Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Diamagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
43.30 nΩ·m
  
99+
Electrical Conductivity
0.01 10
6/cm Ω
  
99+
0.21 10
6/cm Ω
  
8
Electron Affinity
0.00 kJ/mol
  
40
109.70 kJ/mol
  
7
Specific Heat
0.14 J/(kg K)
  
38
0.24 J/(kg K)
  
22
Molar Heat Capacity
27.98 J/mol·K
  
13
24.98 J/mol·K
  
99+
Thermal Conductivity
8.30 W/m·K
  
99+
150.00 W/m·K
  
9
Critical Temperature
Not Available
  
Thermal Expansion
60.40 µm/(m·K)
  
5
8.20 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
56.90 kJ/mol
  
99+
495.40 kJ/mol
  
12
Enthalpy of Fusion
2.29 kJ/mol
  
99+
21.76 kJ/mol
  
10
Enthalpy of Atomization
61.50 kJ/mol
  
99+
556.50 kJ/mol
  
12
Standard Molar Entropy
75.80 J/mol.K
  
6
31.50 J/mol.K
  
99+