Symbol
Pb
  
Rh
  
Period Number
6
  
5
  
Block
p block
  
d block
  
Element Family
Post-Transition
  
Transition Metal
  
Space Group Name
Fm_ 3m
  
Fm_ 3m
  
Interesting Facts
- Galena mineral contains almost 87% of Lead metal in it, Galena is sulfide mineral.
- The best available source of Lead metal today is by recycling automobile batteries.
  
- 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
Earth's crust, Found in Minerals, Mining, Ores of metals, Ores of Minerals
  
Earth's crust, Found As a By-product, Found in Minerals, Mining
  
History
  
  
Who Discovered
Unknown
  
William Hyde Wollaston
  
Discovery
In Middle Easterns (7000 BCE)
  
In 1804
  
Abundance
  
  
Abundance In Sun
~0.000001 %
  
18
~0.0000002 %
  
25
Abundance In Earth's Crust
Abundance In Oceans
Not Available
  
Abundance In Humans
Not Available
  
Uses & Benefits
- It is also used in insecticides, hair dyes and as an anti-knocking additive for petrol. But all these are banned by the government as Lead metal is known for detrimental to health.
  
- 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
Chemical Industry, Electrical Industry, Electronic Industry
  
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
Surgical Instruments Manufacturing
  
NA
  
Other Uses
Alloys
  
Alloys
  
Biological Properties
  
  
Toxicity
Toxic
  
NA
  
Present in Human Body
Yes
  
No
  
In Blood
0.21 Blood/mg dm-3
  
11
Not Available
  
In Bone
30.00 p.p.m.
  
10
Not Available
  
Melting Point
1,966.00 °C
  
12
Boiling Point
1,740.00 °C
  
99+
3,727.00 °C
  
17
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Silvery White
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Vickers Hardness
Not Available
  
1,100.00 MPa
  
9
Speed of Sound
1,190.00 m/s
  
99+
4,700.00 m/s
  
15
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
Pb
  
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
715.60 kJ/mol
  
31
719.70 kJ/mol
  
29
2nd Energy Level
1,450.50 kJ/mol
  
99+
1,740.00 kJ/mol
  
26
3rd Energy Level
3,081.50 kJ/mol
  
23
2,997.00 kJ/mol
  
27
4th Energy Level
4,083.00 kJ/mol
  
35
Not Available
  
5th Energy Level
6,640.00 kJ/mol
  
20
Not Available
  
Electrochemical Equivalent
3.87 g/amp-hr
  
9
1.28 g/amp-hr
  
99+
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes
  
Anti Corrosion, Ionization, Radioactive Isotopes
  
Electron Configuration
[Xe] 4f14 5d10 6s2 6p2
  
[Kr] 4d8 5s1
  
Crystal Structure
Face Centered Cubic (FCC)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
FCC-Crystal-Structure-of-Lead.jpg#100
  
FCC-Crystal-Structure-of-Rhodium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
102.91 amu
  
99+
Atomic Volume
18.17 cm3/mol
  
27
8.30 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
24.20 (-eV)
  
99+
64.00 (-eV)
  
22
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
11.34 g/cm3
  
33
12.41 g/cm3
  
28
Density When Liquid (at m.p.)
10.66 g/cm3
  
15
10.70 g/cm3
  
14
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable
  
Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Diamagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Poor Conductor
  
Conductor
  
Resistivity
208.00 nΩ·m
  
16
43.30 nΩ·m
  
99+
Electrical Conductivity
0.05 106/cm Ω
  
36
0.21 106/cm Ω
  
8
Electron Affinity
35.10 kJ/mol
  
28
109.70 kJ/mol
  
7
Specific Heat
0.13 J/(kg K)
  
39
0.24 J/(kg K)
  
22
Molar Heat Capacity
26.65 J/mol·K
  
26
24.98 J/mol·K
  
99+
Thermal Conductivity
35.30 W/m·K
  
38
150.00 W/m·K
  
9
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
28.90 µm/(m·K)
  
13
8.20 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
179.40 kJ/mol
  
99+
495.40 kJ/mol
  
12
Enthalpy of Fusion
4.77 kJ/mol
  
99+
21.76 kJ/mol
  
10
Enthalpy of Atomization
194.60 kJ/mol
  
99+
556.50 kJ/mol
  
12
Standard Molar Entropy
64.80 J/mol.K
  
17
31.50 J/mol.K
  
99+