Symbol
Cr
  
Cf
  
Group Number
Not Available
  
Period Number
4
  
7
  
Block
d block
  
f block
  
Element Family
Transition Metal
  
Actinide
  
Space Group Name
Im_ 3m
  
P63/mmc
  
Interesting Facts
- 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.
  
- Californium metal is very harmful and highly radioactive.
- Californium metal is the heaviest metal.
  
Sources
Found in Minerals, Mining, Ores of metals, Ores of Minerals
  
Made by Bombarding Curium with Helium Ions
  
History
  
  
Who Discovered
Louis Nicolas Vauquelin
  
Lawrence Berkeley National Laboratory
  
Discovery
In Between 1797 - 1798
  
In 1950
  
Abundance
  
  
Abundance In Universe
1.5 * 10
-3 %
  
7
Not Available
  
Abundance In Sun
~-9999 %
  
Abundance In Meteorites
Not Available
  
Abundance In Earth's Crust
Not Available
  
Abundance In Oceans
Not Available
  
Abundance In Humans
Not Available
  
Uses & Benefits
- 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.
  
- Californium metal has a very strong neutron emitter. It is used as a metal detector.
-
It also used as an identifier to check Water and oil layers in oil wells.
  
Industrial Uses
Automobile Industry, Chemical Industry
  
Chemical Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys
  
Alloys, Nuclear Research
  
Biological Properties
  
  
Toxicity
Highly Toxic
  
Toxic
  
Present in Human Body
Yes
  
No
  
In Blood
0.11 Blood/mg dm-3
  
12
0.00 Blood/mg dm-3
  
37
In Bone
0.33 p.p.m.
  
21
0.00 p.p.m.
  
36
Melting Point
1,857.00 °C
  
14
Boiling Point
2,672.00 °C
  
39
1,470.00 °C
  
99+
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silver
  
Silver
  
Luster
Metallic
  
NA
  
Hardness
  
  
Brinell Hardness
Not Available
  
Vickers Hardness
1,060.00 MPa
  
10
Not Available
  
Speed of Sound
5,940.00 m/s
  
5
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
Cr
  
Cf
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Allen Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
26,130.00 kJ/mol
  
1
608.00 kJ/mol
  
99+
2nd Energy Level
28,750.00 kJ/mol
  
1
1,206.00 kJ/mol
  
99+
3rd Energy Level
34,230.00 kJ/mol
  
1
2,267.00 kJ/mol
  
99+
4th Energy Level
37,066.00 kJ/mol
  
1
3,599.00 kJ/mol
  
99+
5th Energy Level
97,510.00 kJ/mol
  
1
Not Available
  
6th Energy Level
105,800.00 kJ/mol
  
1
Not Available
  
7th Energy level
114,300.00 kJ/mol
  
1
Not Available
  
8th Energy Level
125,300.00 kJ/mol
  
1
Not Available
  
9th Energy Level
134,700.00 kJ/mol
  
1
Not Available
  
10th Energy Level
144,300.00 kJ/mol
  
1
Not Available
  
11th Energy Level
26,130.00 kJ/mol
  
12
Not Available
  
12th Energy Level
28,750.00 kJ/mol
  
13
Not Available
  
13th Energy Level
34,230.00 kJ/mol
  
10
Not Available
  
14th Energy Level
37,066.00 kJ/mol
  
12
Not Available
  
15th Energy Level
97,510.00 kJ/mol
  
1
Not Available
  
16th Energy Level
105,800.00 kJ/mol
  
2
Not Available
  
17th Energy Level
114,300.00 kJ/mol
  
3
Not Available
  
18th Energy Level
125,300.00 kJ/mol
  
4
Not Available
  
19th Energy Level
134,700.00 kJ/mol
  
5
Not Available
  
20th Energy Level
144,300.00 kJ/mol
  
7
Not Available
  
21st Energy Level
157,700.00 kJ/mol
  
7
Not Available
  
22nd Energy Level
166,090.00 kJ/mol
  
6
Not Available
  
Electrochemical Equivalent
0.32 g/amp-hr
  
99+
3.12 g/amp-hr
  
15
Electron Work Function
Not Available
  
Other Chemical Properties
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility
  
Corrosion, Ionization, Radioactive Isotopes, Radioactivity, Solubility
  
Electron Configuration
[Ar] 3d5 4s1
  
[Rn] 5f10 7s2
  
Crystal Structure
Body Centered Cubic (BCC)
  
Double Hexagonal Close Packed (DHCP)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
DHCP-Crystal-Structure-of-Californium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Covalent Radius
Not Available
  
Van der Waals Radius
Not Available
  
Atomic Volume
7.23 cm3/mol
  
99+
Not Available
  
Adjacent Atomic Numbers
  
  
Valence Electron Potential
170.00 (-eV)
  
4
44.50 (-eV)
  
38
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, 2 π/3
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
7.19 g/cm3
  
99+
15.10 g/cm3
  
21
Density When Liquid (at m.p.)
Not Available
  
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Shear Modulus
Not Available
  
Bulk Modulus
Not Available
  
Young's Modulus
Not Available
  
Poisson Ratio
Not Available
  
Other Mechanical Properties
NA
  
Malleable, Sectile
  
Magnetic Characteristics
  
  
Magnetic Ordering
Antiferromagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
NA
  
Unknown
  
Resistivity
125.00 nΩ·m
  
27
Not Available
  
Electrical Conductivity
0.08 10
6/cm Ω
  
25
Not Available
  
Electron Affinity
64.30 kJ/mol
  
15
Not Available
  
Specific Heat
0.45 J/(kg K)
  
12
Not Available
  
Molar Heat Capacity
23.35 J/mol·K
  
99+
Not Available
  
Thermal Conductivity
93.90 W/m·K
  
17
Not Available
  
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
4.90 µm/(m·K)
  
99+
Not Available
  
Enthalpy
  
  
Enthalpy of Vaporization
348.80 kJ/mol
  
24
Not Available
  
Enthalpy of Fusion
15.31 kJ/mol
  
20
Not Available
  
Enthalpy of Atomization
397.50 kJ/mol
  
21
Not Available
  
Standard Molar Entropy
23.80 J/mol.K
  
99+
Not Available