Symbol
Ac
  
Md
  
Group Number
Not Available
  
Not Available
  
Period Number
7
  
7
  
Block
f block
  
f block
  
Element Family
Actinide
  
Actinide
  
Space Group Name
Fm_ 3m
  
Not Available
  
Space Group Number
Not Available
  
Interesting Facts
Not Available
  
- Mendelevium metal is synthetically produced metal.
- Mendelevium metal has been produced in only trace amount.
  
Sources
Obtained by Treating Radium with Neutrons, Ores of metals
  
Bombarding Einsteinium with Helium Ions
  
History
  
  
Who Discovered
Friedrich Oskar Giesel
  
Lawrence Berkeley National Laboratory
  
Discovery
In 1902
  
In 1955
  
Abundance
  
  
Uses & Benefits
- Actinium metal has a great source of alpha rays but it is hardly used outside research purpose.
  
- Currently known uses of Mendelevium metal are limited to research purpose only.
  
Industrial Uses
NA
  
NA
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys, Nuclear Research, Research Purposes
  
NA
  
Biological Properties
  
  
Toxicity
Toxic
  
Unknown
  
Present in Human Body
No
  
No
  
In Blood
0.00 Blood/mg dm-3
  
37
0.00 Blood/mg dm-3
  
37
In Bone
0.00 p.p.m.
  
36
0.00 p.p.m.
  
36
Melting Point
1,227.00 °C
  
38
Boiling Point
3,200.00 °C
  
26
Not Available
  
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery White
  
Unknown
  
Luster
NA
  
Metallic
  
Hardness
  
  
Speed of Sound
Not Available
  
Not Available
  
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
Ac
  
Md
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Allred Rochow Electronegativity
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
499.00 kJ/mol
  
99+
635.00 kJ/mol
  
99+
2nd Energy Level
1,170.00 kJ/mol
  
99+
1,235.00 kJ/mol
  
99+
3rd Energy Level
1,900.00 kJ/mol
  
99+
2,470.00 kJ/mol
  
99+
4th Energy Level
4,700.00 kJ/mol
  
23
3,840.00 kJ/mol
  
99+
Electrochemical Equivalent
2.82 g/amp-hr
  
18
3.21 g/amp-hr
  
12
Electron Work Function
Not Available
  
Not Available
  
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
  
Ionization, Radioactive Isotopes, Radioactivity
  
Electron Configuration
[Rn] 6d1 7s2
  
[Rn] 5f13 7s2
  
Crystal Structure
Face Centered Cubic (FCC)
  
Not Known
  
Crystal Lattice
FCC-Crystal-Structure-of-Actinium.jpg#100
  
Unknown-Crystal-Structure-of-Mendelevium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Radius
Not Available
  
Van der Waals Radius
Not Available
  
Atomic Volume
22.54 cm3/mol
  
11
Not Available
  
Adjacent Atomic Numbers
  
  
Valence Electron Potential
38.60 (-eV)
  
99+
Not Available
  
Lattice Constant
Not Available
  
Lattice Angles
π/2, π/2, π/2
  
NA
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
10.00 g/cm
3
  
37
Not Available
  
Tensile Strength
Not Available
  
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Elasticity properties
  
  
Poisson Ratio
Not Available
  
Not Available
  
Other Mechanical Properties
NA
  
Unknown
  
Magnetic Characteristics
  
  
Specific Gravity
Not Available
  
Magnetic Ordering
Paramagnetic
  
Unknown
  
Electrical Properties
  
  
Specific Heat
0.12 J/(kg K)
  
40
Not Available
  
Molar Heat Capacity
27.20 J/mol·K
  
18
Not Available
  
Thermal Conductivity
12.00 W/m·K
  
99+
Not Available
  
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
Not Available
  
Not Available
  
Enthalpy
  
  
Enthalpy of Atomization
301.00 kJ/mol
  
36
Not Available
  
Standard Molar Entropy
56.50 J/mol.K
  
25
Not Available