Symbol
Er
Cm
Group Number
33
0
17
👆🏻
Period Number
67
2
7
👆🏻
Block
f block
f block
Element Family
Lanthanide
Actinide
CAS Number
74405207440519
7429905
54386242
👆🏻
Space Group Name
P63/mmc
-
Space Group Number
194.00225.00
11
276
👆🏻
Interesting Facts
- Erbium metal is used as alloyed with Vanadium to make it softer.
- Recent studies shows that it is helpful for metabolism.
- Curium metal does not occur free in nature.
- Curium metal is a synthetically produced metal.
Sources
Mining
Bombarding Plutonium with Helium Ions
History
Who Discovered
Carl Gustaf Mosander
Glenn T. Seaborg, Ralph A. James, Albert Ghiorso
Discovery
In 1842
In 1944
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
0.00 %0.00 %
0
0.1
👆🏻
Abundance In Meteorites
0.00 %0.00 %
0
22
👆🏻
Abundance In Earth's Crust
0.00 %0.00 %
1E-37
8.1
👆🏻
Abundance In Oceans
0.00 %-
0
1.1
👆🏻
Abundance In Humans
0.00 %0.00 %
0
1.4
👆🏻
Uses & Benefits
- It has a tendency to get tarnished in the open air, but when alloyed with elements like erbium, vanadium, its hardness levels decreases.
- Its compounds like Erbium oxide is used in safety glasses of welders and metal workers.
- Curium metal is used to provide power to electrical equipment for space missions.
Industrial Uses
Chemical Industry
-
Medical Uses
-
-
Other Uses
Alloys
Research Purposes
Biological Properties
Toxicity
Mildly Toxic
-
Present in Human Body
✔
✘
✔
✘
In Blood
0.00 Blood/mg dm-30.00 Blood/mg dm-3
0
1970
👆🏻
In Bone
0.00 p.p.m.0.00 p.p.m.
0
170000
👆🏻
Melting Point
1,522.00 °C1,340.00 °C
-38.83
3410
👆🏻
Boiling Point
2,510.00 °C3,110.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery White
Silver
Luster
Lustrous
Metallic
Hardness
Mohs Hardness
1.002.00
0.2
8.5
👆🏻
Brinell Hardness
814.00 MPa320.00 MPa
0.14
3490
👆🏻
Vickers Hardness
589.00 MPa461.00 MPa
0
3920
👆🏻
Speed of Sound
2,830.00 m/s2,260.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.761.30
0.155
3.41
👆🏻
Reflectivity
36.00 %60.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Er
Cm
Isotopes
Known Isotopes
3115
0
38
👆🏻
Electronegativity
Pauling Electronegativity
1.241.30
0
2.6
👆🏻
Sanderson Electronegativity
1.241.30
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.111.20
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.241.30
0.62
2.48
👆🏻
Allen Electronegativity
1.241.30
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.762.70
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
589.30 kJ/mol581.00 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
1,150.00 kJ/mol1,196.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
2,194.00 kJ/mol2,026.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
4,120.00 kJ/mol3,550.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
5,897.00 kJ/mol5,810.00 kJ/mol
392
97510
👆🏻
6th Energy Level
5,897.00 kJ/mol5,810.00 kJ/mol
1007
105800
👆🏻
7th Energy level
5,890.00 kJ/mol5,810.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
5,890.00 kJ/mol5,810.00 kJ/mol
730
125300
👆🏻
9th Energy Level
4,240.00 kJ/mol6,690.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
5,890.00 kJ/mol5,810.00 kJ/mol
392
144300
👆🏻
11th Energy Level
5,890.00 kJ/mol5,810.00 kJ/mol
392
169988
👆🏻
12th Energy Level
5,890.00 kJ/mol58,100.00 kJ/mol
0
189368
👆🏻
13th Energy Level
5,890.00 kJ/mol5,810.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
5,890.00 kJ/mol5,810.00 kJ/mol
380
86450
👆🏻
15th Energy Level
58,900.00 kJ/mol58,100.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
58,900.00 kJ/mol58,100.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
589.30 kJ/mol581.00 kJ/mol
375.7
122200
👆🏻
18th Energy Level
5,890.00 kJ/mol5,810.00 kJ/mol
0
134810
👆🏻
19th Energy Level
589.30 kJ/mol581.00 kJ/mol
375.7
148700
👆🏻
20th Energy Level
589.00 kJ/mol581.00 kJ/mol
0
171200
👆🏻
21st Energy Level
5,897.00 kJ/mol5,810.00 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
589.00 kJ/mol581.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
589.30 kJ/mol5,810.00 kJ/mol
357.6
198800
👆🏻
24th Energy Level
589.30 kJ/mol581.00 kJ/mol
297.3
195200
👆🏻
25th Energy Level
589.00 kJ/mol581.00 kJ/mol
0
121900
👆🏻
26th Energy Level
589.30 kJ/mol581.00 kJ/mol
357.6
127700
👆🏻
27th Energy Level
589.30 kJ/mol581.00 kJ/mol
0
133800
👆🏻
28th Energy Level
589.30 kJ/mol581.00 kJ/mol
297.3
139800
👆🏻
29th Energy Level
589.30 kJ/mol581.00 kJ/mol
0
148100
👆🏻
30th Energy Level
589.70 kJ/mol581.00 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
2.08 g/amp-hr3.07 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
5.93 eV4.50 eV
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes, Solubility
Ionization, Radioactive Isotopes
Atomic Number
6896
3
117
👆🏻
Electron Configuration
[Xe] 4f12 6s2
[Rn] 5f7 6d1 7s2
Crystal Structure
Hexagonal Close Packed (HCP)
Double Hexagonal Close Packed (DHCP)
Crystal Lattice
Atom
Number of Protons
6896
3
117
👆🏻
Number of Neutrons
99151
4
285
👆🏻
Number of Electrons
6896
3
117
👆🏻
Radius of an Atom
Atomic Radius
176.00 pm174.00 pm
0
348
👆🏻
Covalent Radius
189.00 pm169.00 pm
0
260
👆🏻
Van der Waals Radius
0.00 pm200.00 pm
0
348
👆🏻
Atomic Weight
167.26 amu247.00 amu
6.94
294
👆🏻
Atomic Volume
18.40 cm3/mol18.28 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
49.00 (-eV)44.50 (-eV)
0
392.42
👆🏻
Lattice Constant
355.88 pm336.25 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, 2 π/3
-
Lattice C/A Ratio
1.571.67
0.423
1.9
👆🏻
Density
Density At Room Temperature
9.07 g/cm313.51 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
8.86 g/cm313.85 g/cm3
0.512
41
👆🏻
Tensile Strength
350.00 MPa350.00 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)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
28.30 GPa32.00 GPa
1.3
222
👆🏻
Bulk Modulus
44.40 GPa40.00 GPa
0
462
👆🏻
Young's Modulus
69.90 GPa0.00 GPa
0
528
👆🏻
Poisson Ratio
0.240.35
0.032
0.47
👆🏻
Other Mechanical Properties
Malleable
-
Magnetic Characteristics
Specific Gravity
9.0713.51
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
0.86 nΩ·m1.25 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.01 106/cm Ω0.13 106/cm Ω
0
0.63
👆🏻
Electron Affinity
50.00 kJ/mol0.00 kJ/mol
0
222.8
👆🏻
Specific Heat
0.17 J/(kg K)0.10 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
28.12 J/mol·K27.50 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
14.50 W/m·K11.00 W/m·K
0
429
👆🏻
Critical Temperature
1,802.00 K1,340.00 K
26.3
3695
👆🏻
Thermal Expansion
12.20 µm/(m·K)11.60 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
261.00 kJ/mol331.60 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
17.20 kJ/mol15.00 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
314.00 kJ/mol-
61.5
837
👆🏻
Standard Molar Entropy
73.10 J/mol.K52.50 J/mol.K
9.5
198.1
👆🏻