Symbol
Ho
  
Cr
  
Group Number
Not Available
  
Period Number
6
  
4
  
Block
f block
  
d block
  
Element Family
Lanthanide
  
Transition Metal
  
Space Group Name
P63/mmc
  
Im_ 3m
  
Interesting Facts
- Holmium metal is very soft and malleable.
- Holmium metal is well known for its corrosion resistivity.
  
- Chromium is highly reactive, hence it is not found free in nature.
- Ores of Chromites mineral are the major source of Chromium metal.
- Almost 90% leather tanning is done with the help of chromium.
  
Sources
Found in Minerals, Mining, Ores of Minerals
  
Found in Minerals, Mining, Ores of metals, Ores of Minerals
  
History
  
  
Who Discovered
Marc Delafontaine
  
Louis Nicolas Vauquelin
  
Discovery
In 1878
  
In Between 1797 - 1798
  
Abundance
  
  
Abundance In Universe
1.5 * 10-3 %
  
7
Abundance In Sun
~-9999 %
  
Abundance In Earth's Crust
Abundance In Humans
Not Available
  
Uses & Benefits
- Holmium metal has an ability to absorb neutrons, so this metal is used in nuclear reactors to keep the chain reactions of elements under control.
-
Alloys of Holmium are used to produce Magnet.
  
- It is used to harden the steel and produces a stainless steel and other various alloys.
- It is also used to give proper finish to polished mirrors. Its chromium plates are used in bathroom fittings.
  
Industrial Uses
NA
  
Automobile Industry, Chemical Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys, Nuclear Research
  
Alloys
  
Biological Properties
  
  
Toxicity
Low Toxic
  
Highly Toxic
  
Present in Human Body
No
  
Yes
  
In Blood
Not Available
  
0.11 Blood/mg dm-3
  
12
In Bone
Not Available
  
0.33 p.p.m.
  
21
Melting Point
1,461.00 °C
  
30
1,857.00 °C
  
14
Boiling Point
2,600.00 °C
  
99+
2,672.00 °C
  
39
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery White
  
Silver
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Mohs Hardness
Not Available
  
Vickers Hardness
1,060.00 MPa
  
10
Speed of Sound
2,760.00 m/s
  
30
5,940.00 m/s
  
5
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
Ho
  
Cr
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
581.00 kJ/mol
  
99+
26,130.00 kJ/mol
  
1
2nd Energy Level
1,140.00 kJ/mol
  
99+
28,750.00 kJ/mol
  
1
3rd Energy Level
2,204.00 kJ/mol
  
99+
34,230.00 kJ/mol
  
1
4th Energy Level
4,100.00 kJ/mol
  
34
37,066.00 kJ/mol
  
1
5th Energy Level
Not Available
  
97,510.00 kJ/mol
  
1
6th Energy Level
Not Available
  
105,800.00 kJ/mol
  
1
7th Energy level
Not Available
  
114,300.00 kJ/mol
  
1
8th Energy Level
Not Available
  
125,300.00 kJ/mol
  
1
9th Energy Level
Not Available
  
134,700.00 kJ/mol
  
1
10th Energy Level
Not Available
  
144,300.00 kJ/mol
  
1
11th Energy Level
Not Available
  
26,130.00 kJ/mol
  
12
12th Energy Level
Not Available
  
28,750.00 kJ/mol
  
13
13th Energy Level
Not Available
  
34,230.00 kJ/mol
  
10
14th Energy Level
Not Available
  
37,066.00 kJ/mol
  
12
15th Energy Level
Not Available
  
97,510.00 kJ/mol
  
1
16th Energy Level
Not Available
  
105,800.00 kJ/mol
  
2
17th Energy Level
Not Available
  
114,300.00 kJ/mol
  
3
18th Energy Level
Not Available
  
125,300.00 kJ/mol
  
4
19th Energy Level
Not Available
  
134,700.00 kJ/mol
  
5
20th Energy Level
Not Available
  
144,300.00 kJ/mol
  
7
21st Energy Level
Not Available
  
157,700.00 kJ/mol
  
7
22nd Energy Level
Not Available
  
166,090.00 kJ/mol
  
6
Electrochemical Equivalent
2.02 g/amp-hr
  
29
0.32 g/amp-hr
  
99+
Electron Work Function
Not Available
  
Other Chemical Properties
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Xe] 4f11 6s2
  
[Ar] 3d5 4s1
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Body Centered Cubic (BCC)
  
Crystal Lattice
HCP-Crystal-Structure-of-Holmium.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
164.93 amu
  
99+
Atomic Volume
18.70 cm3/mol
  
24
7.23 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
47.90 (-eV)
  
31
170.00 (-eV)
  
4
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Density
  
  
Density At Room Temperature
8.79 g/cm3
  
99+
7.19 g/cm3
  
99+
Density When Liquid (at m.p.)
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Ductile, Malleable, Sectile
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Antiferromagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
NA
  
Resistivity
125.00 nΩ·m
  
27
Electrical Conductivity
0.01 106/cm Ω
  
99+
0.08 106/cm Ω
  
25
Electron Affinity
50.00 kJ/mol
  
21
64.30 kJ/mol
  
15
Specific Heat
0.16 J/(kg K)
  
35
0.45 J/(kg K)
  
12
Molar Heat Capacity
27.15 J/mol·K
  
19
23.35 J/mol·K
  
99+
Thermal Conductivity
16.20 W/m·K
  
99+
93.90 W/m·K
  
17
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
11.20 µm/(m·K)
  
35
4.90 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
241.00 kJ/mol
  
38
348.80 kJ/mol
  
24
Enthalpy of Fusion
11.76 kJ/mol
  
29
15.31 kJ/mol
  
20
Enthalpy of Atomization
301.00 kJ/mol
  
36
397.50 kJ/mol
  
21
Standard Molar Entropy
75.30 J/mol.K
  
8
23.80 J/mol.K
  
99+