Properties of Promethium and Silver
Melting Point
1,042.00 °C
  
99+
Boiling Point
3,000.00 °C
  
31
2,212.00 °C
  
99+
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
Not Available
  
Vickers Hardness
Not Available
  
Optical Properties
  
  
Refractive Index
Not Available
  
Not Available
  
Reflectivity
Not Available
  
Speed of Sound
Not Available
  
2,680.00 m/s
  
34
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Pm
  
Ag
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Not Available
  
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Not Available
  
Ionization Energies
  
  
1st Energy Level
540.00 kJ/mol
  
99+
731.00 kJ/mol
  
27
2nd Energy Level
1,050.00 kJ/mol
  
99+
2,070.00 kJ/mol
  
11
3rd Energy Level
2,150.00 kJ/mol
  
99+
3,361.00 kJ/mol
  
19
Electrochemical Equivalent
1.80 g/amp-hr
  
36
4.02 g/amp-hr
  
7
Electron Work Function
Not Available
  
Other Chemical Properties
Density
  
  
Density At Room Temperature
7.26 g/cm3
  
99+
10.49 g/cm3
  
35
Density When Liquid (at m.p.)
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Vapor Pressure at 2000 K
Not Available
  
Not Available
  
Tensile Strength
Not Available
  
Not Available
  
Viscosity
Not Available
  
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
NA
  
Symbol
Pm
  
Ag
  
Group Number
Not Available
  
Period Number
6
  
5
  
Atomic Weight
145.00 amu
  
99+
107.87 amu
  
99+
Atomic Volume
22.39 cm3/mol
  
12
10.30 cm3/mol
  
99+
Electron Configuration
[Xe] 4f5 6s2
  
[Kr] 4d10 5s1
  
Valence Electron Potential
44.10 (-eV)
  
39
11.40 (-eV)
  
99+
Atom
  
  
Crystal Lattice
DHCP-Crystal-Structure-of-Promethium.jpg#100
  
FCC-Crystal-Structure-of-Silver.jpg#100
  
Radius of an Atom
  
  
Lattice Constant
Not Available
  
Lattice Angles
Unknown
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Adjacent Atomic Numbers
  
  
Electrical Properties
  
  
Resistivity
15.87 nΩ·m
  
99+
Electrical Conductivity
Not Available
  
0.63 10
6/cm Ω
  
1
Electron Affinity
50.00 kJ/mol
  
21
125.60 kJ/mol
  
5
Magnetic Characteristics
  
  
Permeability
Not Available
  
Not Available
  
Susceptibility
Not Available
  
Specific Heat
0.18 J/(kg K)
  
33
0.24 J/(kg K)
  
25
Thermal Conductivity
17.90 W/m·K
  
99+
429.00 W/m·K
  
1
Critical Temperature
Not Available
  
Not Available
  
Molar Heat Capacity
Not Available
  
25.35 J/mol·K
  
99+
Thermal Expansion
9.00 µm/(m·K)
  
99+
18.90 µm/(m·K)
  
23
Standard Molar Entropy
Not Available
  
42.60 J/mol.K
  
35
Enthalpy
  
  
Enthalpy of Vaporization
Not Available
  
255.10 kJ/mol
  
37
Enthalpy of Fusion
7.50 kJ/mol
  
99+
11.30 kJ/mol
  
31
Enthalpy of Atomization
310.00 kJ/mol
  
34
284.50 kJ/mol
  
37