Home
Compare Metals


Erbium vs Actinium


Actinium vs Erbium


Periodic Table

Symbol
Er  
Ac  

Group Number
3  
15
3  
15

Period Number
6  
7  

Block
f block  
f block  

Element Family
Lanthanide  
Actinide  

CAS Number
7440520  
35
7440348  
99+

Space Group Name
P63/mmc  
Fm_ 3m  

Space Group Number
194.00  
7
225.00  
3

Facts

Interesting Facts
  • Erbium metal is used as alloyed with Vanadium to make it softer.
  • Recent studies shows that it is helpful for metabolism.
  
Actinium glows in the dark due to its radioactivity.  

Sources
Mining  
Obtained by Treating Radium with Neutrons, Ores of metals  

History
  
  

Who Discovered
Carl Gustaf Mosander  
Friedrich Oskar Giesel  

Discovery
In 1842  
In 1902  

Abundance
  
  

Abundance In Universe
0.00 %  
23
0.00 %  
34

Abundance In Sun
0.00 %  
26
0.00 %  
26

Abundance In Meteorites
0.00 %  
36
0.00 %  
99+

Abundance In Earth's Crust
0.00 %  
32
0.00 %  
99+

Abundance In Oceans
0.00 %  
36
0.00 %  
99+

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

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.
  
  • Actinium metal has a great source of alpha rays but it is hardly used outside research purpose.
  

Industrial Uses
Chemical Industry  
-  

Medical Uses
-  
-  

Other Uses
Alloys  
Alloys, Nuclear Research, Research Purposes  

Biological Properties
  
  

Toxicity
Mildly Toxic  
Toxic  

Present in Human Body
No  
No  

In Blood
0.00 Blood/mg dm-3  
40
0.00 Blood/mg dm-3  
40

In Bone
0.00 p.p.m.  
99+
0.00 p.p.m.  
99+

Physical

Melting Point
1,522.00 °C  
28
1,227.00 °C  
38

Boiling Point
2,510.00 °C  
99+
3,200.00 °C  
27

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery White  
Silvery White  

Luster
Lustrous  
-  

Hardness
  
  

Mohs Hardness
1.00  
22
6.50  
5

Brinell Hardness
814.00 MPa  
12
70.00 MPa  
99+

Vickers Hardness
589.00 MPa  
30
260.00 MPa  
99+

Speed of Sound
2,830.00 m/s  
99+
3,430.00 m/s  
32

Optical Properties
  
  

Refractive Index
1.76  
24
1.00  
99+

Reflectivity
36.00 %  
33
62.00 %  
21

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Er  
Ac  

Isotopes
  
  

Known Isotopes
31  
8
29  
10

Electronegativity
  
  

Pauling Electronegativity
1.24  
37
1.10  
99+

Sanderson Electronegativity
1.24  
29
1.10  
38

Allred Rochow Electronegativity
1.11  
30
1.00  
37

Mulliken-Jaffe Electronegativity
1.24  
36
1.10  
99+

Allen Electronegativity
1.24  
99+
1.10  
99+

Electropositivity
  
  

Pauling Electropositivity
2.76  
18
2.90  
10

Ionization Energies
  
  

1st Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

2nd Energy Level
1,150.00 kJ/mol  
99+
1,170.00 kJ/mol  
99+

3rd Energy Level
2,194.00 kJ/mol  
99+
1,900.00 kJ/mol  
99+

4th Energy Level
4,120.00 kJ/mol  
99+
4,700.00 kJ/mol  
33

5th Energy Level
5,897.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

6th Energy Level
5,897.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

7th Energy level
5,890.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

8th Energy Level
5,890.00 kJ/mol  
99+
5,750.00 kJ/mol  
99+

9th Energy Level
4,240.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

10th Energy Level
5,890.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

11th Energy Level
5,890.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

12th Energy Level
5,890.00 kJ/mol  
99+
49,900.00 kJ/mol  
21

13th Energy Level
5,890.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

14th Energy Level
5,890.00 kJ/mol  
37
4,990.00 kJ/mol  
99+

15th Energy Level
58,900.00 kJ/mol  
99+
49,900.00 kJ/mol  
99+

16th Energy Level
58,900.00 kJ/mol  
38
49,900.00 kJ/mol  
99+

17th Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

18th Energy Level
5,890.00 kJ/mol  
99+
4,990.00 kJ/mol  
99+

19th Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

20th Energy Level
589.00 kJ/mol  
99+
499.00 kJ/mol  
99+

21st Energy Level
5,897.00 kJ/mol  
19
4,990.00 kJ/mol  
25

22nd Energy Level
589.00 kJ/mol  
99+
499.00 kJ/mol  
99+

23rd Energy Level
589.30 kJ/mol  
99+
4,990.00 kJ/mol  
29

24th Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

25th Energy Level
589.00 kJ/mol  
99+
499.00 kJ/mol  
99+

26th Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

27th Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

28th Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

29th Energy Level
589.30 kJ/mol  
99+
499.00 kJ/mol  
99+

30th Energy Level
589.70 kJ/mol  
99+
499.00 kJ/mol  
99+

Electrochemical Equivalent
2.08 g/amp-hr  
32
2.82 g/amp-hr  
22

Electron Work Function
5.93 eV  
2
4.38 eV  
23

Other Chemical Properties
Ionization, Radioactive Isotopes, Solubility  
Ionization, Radioactive Isotopes, Radioactivity, Solubility  

Atomic

Atomic Number
68  
99+
89  
29

Electron Configuration
[Xe] 4f12 6s2  
[Rn] 6d1 7s2  

Crystal Structure
Hexagonal Close Packed (HCP)  
Face Centered Cubic (FCC)  

Crystal Lattice
HCP-Crystal-Structure-of-Erbium.jpg#100  
FCC-Crystal-Structure-of-Actinium.jpg#100  

Atom
  
  

Number of Protons
68  
99+
89  
29

Number of Neutrons
99  
34
138  
17

Number of Electrons
68  
99+
89  
29

Radius of an Atom
  
  

Atomic Radius
176.00 pm  
20
195.00 pm  
9

Covalent Radius
189.00 pm  
19
186.00 pm  
21

Van der Waals Radius
0.00 pm  
99+
215.00 pm  
31

Atomic Weight
167.26 amu  
99+
227.00 amu  
25

Atomic Volume
18.40 cm3/mol  
37
22.54 cm3/mol  
20

Adjacent Atomic Numbers
  
  

Previous Element
Holmium
  
Radium
  

Next Element
Thulium
  
Thorium
  

Valence Electron Potential
49.00 (-eV)  
30
38.60 (-eV)  
99+

Lattice Constant
355.88 pm  
99+
567.00 pm  
9

Lattice Angles
π/2, π/2, 2 π/3  
π/2, π/2, π/2  

Lattice C/A Ratio
1.57  
40
1.89  
2

Mechanical

Density
  
  

Density At Room Temperature
9.07 g/cm3  
99+
10.00 g/cm3  
40

Density When Liquid (at m.p.)
8.86 g/cm3  
99+
10.07 g/cm3  
40

Tensile Strength
350.00 MPa  
12
65.00 MPa  
33

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
21
0.00 (Pa)  
22

Vapor Pressure at 2000 K
0.00 (Pa)  
30
0.00 (Pa)  
30

Elasticity properties
  
  

Shear Modulus
28.30 GPa  
31
25.00 GPa  
38

Bulk Modulus
44.40 GPa  
31
94.00 GPa  
17

Young's Modulus
69.90 GPa  
31
130.00 GPa  
16

Poisson Ratio
0.24  
28
0.34  
10

Other Mechanical Properties
Malleable  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
9.07  
99+
10.07  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
17
0.00 H/m  
17

Susceptibility
0.00  
11
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
-  

Resistivity
0.86 nΩ·m  
99+
5.20 nΩ·m  
99+

Electrical Conductivity
0.01 106/cm Ω  
99+
0.15 106/cm Ω  
13

Electron Affinity
50.00 kJ/mol  
26
33.20 kJ/mol  
34

Thermal

Specific Heat
0.17 J/(kg K)  
35
0.12 J/(kg K)  
99+

Molar Heat Capacity
28.12 J/mol·K  
14
27.20 J/mol·K  
24

Thermal Conductivity
14.50 W/m·K  
99+
12.00 W/m·K  
99+

Critical Temperature
1,802.00 K  
30
1,323.00 K  
99+

Thermal Expansion
12.20 µm/(m·K)  
99+
12.10 µm/(m·K)  
99+

Enthalpy
  
  

Enthalpy of Vaporization
261.00 kJ/mol  
99+
120.00 kJ/mol  
99+

Enthalpy of Fusion
17.20 kJ/mol  
15
14.20 kJ/mol  
28

Enthalpy of Atomization
314.00 kJ/mol  
99+
301.00 kJ/mol  
99+

Standard Molar Entropy
73.10 J/mol.K  
11
56.50 J/mol.K  
33

Periodic Table >>
<< All

Compare Lanthanide Series

Lanthanide Series

Lanthanide Series

» More Lanthanide Series

Compare Lanthanide Series

» More Compare Lanthanide Series