Symbol
Sm
  
Pb
  
Group Number
Not Available
  
Period Number
6
  
6
  
Block
f block
  
p block
  
Element Family
Lanthanide
  
Post-Transition
  
Space Group Name
R_ 3m
  
Fm_ 3m
  
Interesting Facts
- Samarium metals helps stimulating body metabolism.
- Samarium metals was 1st observed by Jean Charles Galissard de Marignac in Dydimia in 1853.
  
- 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.
  
Sources
Found in Minerals, Mining, Ores of Minerals
  
Earth's crust, Found in Minerals, Mining, Ores of metals, Ores of Minerals
  
History
  
  
Who Discovered
Lecoq de Boisbaudran
  
Unknown
  
Discovery
In 1879
  
In Middle Easterns (7000 BCE)
  
Abundance
  
  
Abundance In Sun
~0.0000001 %
  
26
~0.000001 %
  
18
Abundance In Earth's Crust
Abundance In Humans
Not Available
  
Uses & Benefits
- Magnets of Samarium cobalt alloy are stronger than that of Iron and hence, they are used in microwave application.
- Samarium metal also used in optical lasers and infrared absorbing glasses and as a neutron absorber.
  
- 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.
  
Industrial Uses
Aerospace Industry, Automobile Industry, Chemical Industry, Electrical Industry, Electronic Industry
  
Chemical Industry, Electrical Industry, Electronic Industry
  
Medical Uses
NA
  
Surgical Instruments Manufacturing
  
Other Uses
Alloys, In Nuclear Reactors
  
Alloys
  
Biological Properties
  
  
Toxicity
Slightly Toxic
  
Toxic
  
Present in Human Body
Yes
  
Yes
  
In Blood
0.01 Blood/mg dm-3
  
22
0.21 Blood/mg dm-3
  
11
In Bone
Not Available
  
30.00 p.p.m.
  
10
Melting Point
1,072.00 °C
  
99+
Boiling Point
1,900.00 °C
  
99+
1,740.00 °C
  
99+
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery White
  
Gray
  
Luster
Lustrous
  
Metallic
  
Hardness
  
  
Mohs Hardness
Not Available
  
Vickers Hardness
Not Available
  
Speed of Sound
2,130.00 m/s
  
99+
1,190.00 m/s
  
99+
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
Sm
  
Pb
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
544.50 kJ/mol
  
99+
715.60 kJ/mol
  
31
2nd Energy Level
1,070.00 kJ/mol
  
99+
1,450.50 kJ/mol
  
99+
3rd Energy Level
2,260.00 kJ/mol
  
99+
3,081.50 kJ/mol
  
23
4th Energy Level
3,990.00 kJ/mol
  
37
4,083.00 kJ/mol
  
35
5th Energy Level
Not Available
  
6,640.00 kJ/mol
  
20
Electrochemical Equivalent
1.87 g/amp-hr
  
34
3.87 g/amp-hr
  
9
Other Chemical Properties
Ionization, Radioactive Isotopes
  
Anti Corrosion, Ionization, Radioactive Isotopes
  
Electron Configuration
[Xe] 4f6 6s2
  
[Xe] 4f14 5d10 6s2 6p2
  
Crystal Structure
Rhombohedral (RHO)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
RHO-Crystal-Structure-of-Samarium.jpg#100
  
FCC-Crystal-Structure-of-Lead.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
150.36 amu
  
99+
Atomic Volume
19.95 cm3/mol
  
19
18.17 cm3/mol
  
27
Adjacent Atomic Numbers
  
  
Valence Electron Potential
44.80 (-eV)
  
37
24.20 (-eV)
  
99+
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
7.52 g/cm3
  
99+
11.34 g/cm3
  
33
Density When Liquid (at m.p.)
10.66 g/cm3
  
15
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Other Mechanical Properties
NA
  
Ductile, Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Diamagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Poor Conductor
  
Resistivity
208.00 nΩ·m
  
16
Electrical Conductivity
0.01 106/cm Ω
  
99+
0.05 106/cm Ω
  
36
Electron Affinity
50.00 kJ/mol
  
21
35.10 kJ/mol
  
28
Specific Heat
0.20 J/(kg K)
  
31
0.13 J/(kg K)
  
39
Molar Heat Capacity
29.54 J/mol·K
  
7
26.65 J/mol·K
  
26
Thermal Conductivity
13.30 W/m·K
  
99+
35.30 W/m·K
  
38
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
12.70 µm/(m·K)
  
30
28.90 µm/(m·K)
  
13
Enthalpy
  
  
Enthalpy of Vaporization
166.40 kJ/mol
  
99+
179.40 kJ/mol
  
99+
Enthalpy of Fusion
8.62 kJ/mol
  
40
4.77 kJ/mol
  
99+
Enthalpy of Atomization
209.00 kJ/mol
  
99+
194.60 kJ/mol
  
99+
Standard Molar Entropy
69.60 J/mol.K
  
15
64.80 J/mol.K
  
17