Symbol
-
Cr
Group Number
16
0
17
👆🏻
Period Number
34
2
7
👆🏻
Block
s block
d block
Element Family
Alkali
Transition Metal
CAS Number
74402357440473
7429905
54386242
👆🏻
Space Group Name
Im_ 3m
Im_ 3m
Space Group Number
229.00229.00
11
276
👆🏻
Interesting Facts
- At room temperature Sodium metal is very soft as it can be chopped down into pieces with butter knife.
- The most common compound of Sodium is NaCl (Salt).
- 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
By Electrolysis Process, Mining
Found in Minerals, Mining, Ores of metals, Ores of Minerals
History
Who Discovered
Humphry Davy
Louis Nicolas Vauquelin
Discovery
In 1807
In Between 1797 - 1798
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
0.00 %0.00 %
0
0.1
👆🏻
Abundance In Meteorites
0.55 %0.30 %
0
22
👆🏻
Abundance In Earth's Crust
2.30 %0.01 %
1E-37
8.1
👆🏻
Abundance In Oceans
1.10 %0.00 %
0
1.1
👆🏻
Abundance In Humans
0.14 %0.00 %
0
1.4
👆🏻
Uses & Benefits
- In some nuclear reactors sodium is used as a heat exchanger.
- Compound of Sodium metals called Salt (Sodium chloride) is used in Food.
- 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
Electrical Industry, Electronic Industry
Automobile Industry, Chemical Industry
Medical Uses
Pharmaceutical Industry
-
Other Uses
Alloys
Alloys
Biological Properties
Toxicity
Toxic
Highly Toxic
Present in Human Body
✔
✘
✔
✘
In Blood
1,970.00 Blood/mg dm-30.11 Blood/mg dm-3
0
1970
👆🏻
In Bone
10,000.00 p.p.m.0.33 p.p.m.
0
170000
👆🏻
Melting Point
97.72 °C1,857.00 °C
-38.83
3410
👆🏻
Boiling Point
883.00 °C2,672.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery White
Silver
Luster
Metallic
Metallic
Hardness
Mohs Hardness
0.508.50
0.2
8.5
👆🏻
Brinell Hardness
0.69 MPa687.00 MPa
0.14
3490
👆🏻
Vickers Hardness
0.69 MPa1,060.00 MPa
0
3920
👆🏻
Speed of Sound
3,200.00 m/s5,940.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.332.97
0.155
3.41
👆🏻
Reflectivity
53.00 %70.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
-
Cr
Isotopes
Known Isotopes
1721
0
38
👆🏻
Electronegativity
Pauling Electronegativity
0.931.66
0
2.6
👆🏻
Sanderson Electronegativity
0.561.66
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.011.56
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
0.911.66
0.62
2.48
👆🏻
Allen Electronegativity
0.871.65
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
3.072.34
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
495.80 kJ/mol26,130.00 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
4,562.00 kJ/mol28,750.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
6,910.30 kJ/mol34,230.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
9,543.00 kJ/mol37,066.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
13,354.00 kJ/mol97,510.00 kJ/mol
392
97510
👆🏻
6th Energy Level
16,613.00 kJ/mol105,800.00 kJ/mol
1007
105800
👆🏻
7th Energy level
20,117.00 kJ/mol114,300.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
25,496.00 kJ/mol125,300.00 kJ/mol
730
125300
👆🏻
9th Energy Level
28,932.00 kJ/mol134,700.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
141,362.00 kJ/mol144,300.00 kJ/mol
392
144300
👆🏻
11th Energy Level
159,076.00 kJ/mol26,130.00 kJ/mol
392
169988
👆🏻
12th Energy Level
4,950.00 kJ/mol28,750.00 kJ/mol
0
189368
👆🏻
13th Energy Level
4,950.00 kJ/mol34,230.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
495.80 kJ/mol37,066.00 kJ/mol
380
86450
👆🏻
15th Energy Level
49,500.00 kJ/mol97,510.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
49,500.00 kJ/mol105,800.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
495.80 kJ/mol114,300.00 kJ/mol
375.7
122200
👆🏻
18th Energy Level
4,960.00 kJ/mol125,300.00 kJ/mol
0
134810
👆🏻
19th Energy Level
495.80 kJ/mol134,700.00 kJ/mol
375.7
148700
👆🏻
20th Energy Level
496.00 kJ/mol144,300.00 kJ/mol
0
171200
👆🏻
21st Energy Level
495.80 kJ/mol157,700.00 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
495.00 kJ/mol166,090.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
495.80 kJ/mol653.80 kJ/mol
357.6
198800
👆🏻
24th Energy Level
495.80 kJ/mol653.80 kJ/mol
297.3
195200
👆🏻
25th Energy Level
496.00 kJ/mol653.80 kJ/mol
0
121900
👆🏻
26th Energy Level
495.80 kJ/mol653.80 kJ/mol
357.6
127700
👆🏻
27th Energy Level
495.80 kJ/mol652.90 kJ/mol
0
133800
👆🏻
28th Energy Level
495.80 kJ/mol653.80 kJ/mol
297.3
139800
👆🏻
29th Energy Level
495.80 kJ/mol653.80 kJ/mol
0
148100
👆🏻
30th Energy Level
495.80 kJ/mol653.80 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
0.86 g/amp-hr0.32 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
2.75 eV4.50 eV
2.14
6
👆🏻
Other Chemical Properties
Chemical Stability, Corrosion, Flammability, Ionization, Solubility
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility
Atomic Number
1124
3
117
👆🏻
Electron Configuration
[Ne] 3s1
[Ar] 3d5 4s1
Crystal Structure
Body Centered Cubic (BCC)
Body Centered Cubic (BCC)
Crystal Lattice
Atom
Number of Protons
1124
3
117
👆🏻
Number of Neutrons
1228
4
285
👆🏻
Number of Electrons
1124
3
117
👆🏻
Radius of an Atom
Atomic Radius
186.00 pm128.00 pm
0
348
👆🏻
Covalent Radius
166.00 pm139.00 pm
0
260
👆🏻
Van der Waals Radius
227.00 pm200.00 pm
0
348
👆🏻
Atomic Weight
22.99 amu52.00 amu
6.94
294
👆🏻
Atomic Volume
23.70 cm3/mol7.23 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
14.10 (-eV)170.00 (-eV)
0
392.42
👆🏻
Lattice Constant
429.06 pm291.00 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, π/2
π/2, π/2, π/2
Lattice C/A Ratio
1.011.86
0.423
1.9
👆🏻
Density
Density At Room Temperature
0.97 g/cm37.19 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
0.93 g/cm36.30 g/cm3
0.512
41
👆🏻
Tensile Strength
10.00 MPa689.00 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)0.00 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
0.00 (Pa)774.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
3.30 GPa115.00 GPa
1.3
222
👆🏻
Bulk Modulus
6.30 GPa160.00 GPa
0
462
👆🏻
Young's Modulus
10.00 GPa279.00 GPa
0
528
👆🏻
Poisson Ratio
0.370.21
0.032
0.47
👆🏻
Other Mechanical Properties
-
-
Magnetic Characteristics
Specific Gravity
0.977.19
0.53
4500
👆🏻
Magnetic Ordering
Paramagnetic
Antiferromagnetic
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
47.70 nΩ·m125.00 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.21 106/cm Ω0.08 106/cm Ω
0
0.63
👆🏻
Electron Affinity
52.80 kJ/mol64.30 kJ/mol
0
222.8
👆🏻
Specific Heat
1.23 J/(kg K)0.45 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
28.23 J/mol·K23.35 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
142.00 W/m·K93.90 W/m·K
0
429
👆🏻
Critical Temperature
2,573.00 K1,907.00 K
26.3
3695
👆🏻
Thermal Expansion
71.00 µm/(m·K)4.90 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
89.04 kJ/mol348.80 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
2.59 kJ/mol15.31 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
108.40 kJ/mol397.50 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
51.30 J/mol.K23.80 J/mol.K
9.5
198.1
👆🏻