Symbol
Cr
Sm
Group Number
63
0
17
👆🏻
Period Number
46
2
7
👆🏻
Block
d block
f block
Element Family
Transition Metal
Lanthanide
CAS Number
74404737440199
7429905
54386242
👆🏻
Space Group Name
Im_ 3m
R_ 3m
Space Group Number
229.00166.00
11
276
👆🏻
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.
- Samarium metals helps stimulating body metabolism.
- Samarium metals was 1st observed by Jean Charles Galissard de Marignac in Dydimia in 1853.
Sources
Found in Minerals, Mining, Ores of metals, Ores of Minerals
Found in Minerals, Mining, Ores of Minerals
History
Who Discovered
Louis Nicolas Vauquelin
Lecoq de Boisbaudran
Discovery
In Between 1797 - 1798
In 1879
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
0.00 %0.00 %
0
0.1
👆🏻
Abundance In Meteorites
0.30 %0.00 %
0
22
👆🏻
Abundance In Earth's Crust
0.01 %0.00 %
1E-37
8.1
👆🏻
Abundance In Oceans
0.00 %0.00 %
0
1.1
👆🏻
Abundance In Humans
0.00 %0.00 %
0
1.4
👆🏻
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.
- 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.
Industrial Uses
Automobile Industry, Chemical Industry
Aerospace Industry, Automobile Industry, Chemical Industry, Electrical Industry, Electronic Industry
Medical Uses
-
-
Other Uses
Alloys
Alloys, In Nuclear Reactors
Biological Properties
Toxicity
Highly Toxic
Slightly Toxic
Present in Human Body
✔
✘
✔
✘
In Blood
0.11 Blood/mg dm-30.01 Blood/mg dm-3
0
1970
👆🏻
In Bone
0.33 p.p.m.0.00 p.p.m.
0
170000
👆🏻
Melting Point
1,857.00 °C1,072.00 °C
-38.83
3410
👆🏻
Boiling Point
2,672.00 °C1,900.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silver
Silvery White
Luster
Metallic
Lustrous
Hardness
Mohs Hardness
8.505.50
0.2
8.5
👆🏻
Brinell Hardness
687.00 MPa441.00 MPa
0.14
3490
👆🏻
Vickers Hardness
1,060.00 MPa412.00 MPa
0
3920
👆🏻
Speed of Sound
5,940.00 m/s2,130.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
2.971.80
0.155
3.41
👆🏻
Reflectivity
70.00 %65.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Cr
Sm
Isotopes
Known Isotopes
2130
0
38
👆🏻
Electronegativity
Pauling Electronegativity
1.661.17
0
2.6
👆🏻
Sanderson Electronegativity
1.661.17
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.561.07
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.661.17
0.62
2.48
👆🏻
Allen Electronegativity
1.651.17
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.342.83
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
26,130.00 kJ/mol544.50 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
28,750.00 kJ/mol1,070.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
34,230.00 kJ/mol2,260.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
37,066.00 kJ/mol3,990.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
97,510.00 kJ/mol5,445.00 kJ/mol
392
97510
👆🏻
6th Energy Level
105,800.00 kJ/mol5,445.00 kJ/mol
1007
105800
👆🏻
7th Energy level
114,300.00 kJ/mol5,445.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
125,300.00 kJ/mol5,400.00 kJ/mol
730
125300
👆🏻
9th Energy Level
134,700.00 kJ/mol5,440.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
144,300.00 kJ/mol5,445.00 kJ/mol
392
144300
👆🏻
11th Energy Level
26,130.00 kJ/mol5,445.00 kJ/mol
392
169988
👆🏻
12th Energy Level
28,750.00 kJ/mol5,440.00 kJ/mol
0
189368
👆🏻
13th Energy Level
34,230.00 kJ/mol5,445.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
37,066.00 kJ/mol5,450.00 kJ/mol
380
86450
👆🏻
15th Energy Level
97,510.00 kJ/mol54,450.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
105,800.00 kJ/mol54,400.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
114,300.00 kJ/mol544.50 kJ/mol
375.7
122200
👆🏻
18th Energy Level
125,300.00 kJ/mol5,445.00 kJ/mol
0
134810
👆🏻
19th Energy Level
134,700.00 kJ/mol544.50 kJ/mol
375.7
148700
👆🏻
20th Energy Level
144,300.00 kJ/mol624.00 kJ/mol
0
171200
👆🏻
21st Energy Level
157,700.00 kJ/mol544.50 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
166,090.00 kJ/mol624.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
653.80 kJ/mol544.50 kJ/mol
357.6
198800
👆🏻
24th Energy Level
653.80 kJ/mol544.50 kJ/mol
297.3
195200
👆🏻
25th Energy Level
653.80 kJ/mol544.00 kJ/mol
0
121900
👆🏻
26th Energy Level
653.80 kJ/mol544.50 kJ/mol
357.6
127700
👆🏻
27th Energy Level
652.90 kJ/mol544.50 kJ/mol
0
133800
👆🏻
28th Energy Level
653.80 kJ/mol544.50 kJ/mol
297.3
139800
👆🏻
29th Energy Level
653.80 kJ/mol544.50 kJ/mol
0
148100
👆🏻
30th Energy Level
653.80 kJ/mol544.00 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
0.32 g/amp-hr1.87 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
4.50 eV2.70 eV
2.14
6
👆🏻
Other Chemical Properties
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility
Ionization, Radioactive Isotopes
Atomic Number
2462
3
117
👆🏻
Electron Configuration
[Ar] 3d5 4s1
[Xe] 4f6 6s2
Crystal Structure
Body Centered Cubic (BCC)
Rhombohedral (RHO)
Crystal Lattice
Atom
Number of Protons
2462
3
117
👆🏻
Number of Neutrons
2888
4
285
👆🏻
Number of Electrons
2462
3
117
👆🏻
Radius of an Atom
Atomic Radius
128.00 pm180.00 pm
0
348
👆🏻
Covalent Radius
139.00 pm198.00 pm
0
260
👆🏻
Van der Waals Radius
200.00 pm229.00 pm
0
348
👆🏻
Atomic Weight
52.00 amu150.36 amu
6.94
294
👆🏻
Atomic Volume
7.23 cm3/mol19.95 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
170.00 (-eV)44.80 (-eV)
0
392.42
👆🏻
Lattice Constant
291.00 pm362.10 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, π/2
π/2, π/2, 2 π/3
Lattice C/A Ratio
1.861.62
0.423
1.9
👆🏻
Density
Density At Room Temperature
7.19 g/cm37.52 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
6.30 g/cm37.16 g/cm3
0.512
41
👆🏻
Tensile Strength
689.00 MPa50.00 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)0.94 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
774.00 (Pa)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
115.00 GPa19.50 GPa
1.3
222
👆🏻
Bulk Modulus
160.00 GPa37.80 GPa
0
462
👆🏻
Young's Modulus
279.00 GPa49.70 GPa
0
528
👆🏻
Poisson Ratio
0.210.27
0.032
0.47
👆🏻
Other Mechanical Properties
-
-
Magnetic Characteristics
Specific Gravity
7.197.52
0.53
4500
👆🏻
Magnetic Ordering
Antiferromagnetic
Paramagnetic
Permeability
0.00 H/m0.00 H/m
1.25643E-06
0.0063
👆🏻
Susceptibility
0.000.00
-0.000166
200000
👆🏻
Electrical Properties
Electrical Property
-
Conductor
Resistivity
125.00 nΩ·m0.94 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.08 106/cm Ω0.01 106/cm Ω
0
0.63
👆🏻
Electron Affinity
64.30 kJ/mol50.00 kJ/mol
0
222.8
👆🏻
Specific Heat
0.45 J/(kg K)0.20 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
23.35 J/mol·K29.54 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
93.90 W/m·K13.30 W/m·K
0
429
👆🏻
Critical Temperature
1,907.00 K1,345.00 K
26.3
3695
👆🏻
Thermal Expansion
4.90 µm/(m·K)12.70 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
348.80 kJ/mol166.40 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
15.31 kJ/mol8.62 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
397.50 kJ/mol209.00 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
23.80 J/mol.K69.60 J/mol.K
9.5
198.1
👆🏻