Symbol
Hs
Cs
Group Number
81
0
17
👆🏻
Period Number
76
2
7
👆🏻
Block
d block
s block
Element Family
Transition Metal
Alkali
CAS Number
540375797440462
7429905
54386242
👆🏻
Space Group Name
-
Im_ 3m
Space Group Number
166.00229.00
11
276
👆🏻
Interesting Facts
- Hassium metals rate of decay is very high.
- Hassium metals 1st sample was synthesized through a nuclear reaction.
Cesium is the most alkaline metal and is used in atomic clocks.
Sources
Synthetically Produced
Earth's crust, Found in Minerals, Mining, Ores of Minerals
History
Who Discovered
Gesellschaft für Schwerionenforschung
Robert Bunsen and Gustav Kirchhoff
Discovery
In 1984
In 1860
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
-0.00 %
0
0.1
👆🏻
Abundance In Meteorites
0.00 %0.00 %
0
22
👆🏻
Abundance In Earth's Crust
-0.00 %
1E-37
8.1
👆🏻
Abundance In Oceans
-0.00 %
0
1.1
👆🏻
Abundance In Humans
-0.00 %
0
1.4
👆🏻
Uses & Benefits
- Currently known uses of Hassium metal are limited to research purpose only.
- The most common use of cesium metal is as a drilling fluid. It is also used in optical glass manufacturing.
-
In vacuum tubes and radiation monitor equipment this metal is used as a catalyst promoter.
Industrial Uses
-
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
Medical Uses
-
-
Other Uses
Research Purposes
Alloys
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.0.05 p.p.m.
0
170000
👆🏻
Melting Point
-28.50 °C
-38.83
3410
👆🏻
Boiling Point
0.00 °C678.40 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silver
Silvery Gold
Luster
-
-
Hardness
Mohs Hardness
4.500.20
0.2
8.5
👆🏻
Brinell Hardness
230.00 MPa0.14 MPa
0.14
3490
👆🏻
Vickers Hardness
2,450.00 MPa0.14 MPa
0
3920
👆🏻
Speed of Sound
2,760.00 m/s1,630.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.301.93
0.155
3.41
👆🏻
Reflectivity
69.00 %35.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Hs
Cs
Isotopes
Known Isotopes
736
0
38
👆🏻
Electronegativity
Pauling Electronegativity
2.200.79
0
2.6
👆🏻
Sanderson Electronegativity
1.300.22
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.300.86
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.300.62
0.62
2.48
👆🏻
Allen Electronegativity
1.300.66
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.003.21
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
733.30 kJ/mol375.70 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
1,756.00 kJ/mol2,234.30 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
2,827.00 kJ/mol3,400.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
3,637.50 kJ/mol375.70 kJ/mol
375.7
37066
👆🏻
5th Energy Level
4,940.00 kJ/mol3,750.00 kJ/mol
392
97510
👆🏻
6th Energy Level
6,175.10 kJ/mol3,750.00 kJ/mol
1007
105800
👆🏻
7th Energy level
7,535.50 kJ/mol3,750.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
8,857.40 kJ/mol3,760.00 kJ/mol
730
125300
👆🏻
9th Energy Level
5,400.00 kJ/mol3,750.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
6,100.00 kJ/mol3,757.00 kJ/mol
392
144300
👆🏻
11th Energy Level
6,100.00 kJ/mol3,757.00 kJ/mol
392
169988
👆🏻
12th Energy Level
3,500.00 kJ/mol3,750.00 kJ/mol
0
189368
👆🏻
13th Energy Level
4,200.00 kJ/mol3,750.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
1,124.00 kJ/mol3,750.00 kJ/mol
380
86450
👆🏻
15th Energy Level
68,200.00 kJ/mol37,500.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
32,800.00 kJ/mol375.70 kJ/mol
375.7
109480
👆🏻
17th Energy Level
1,089.00 kJ/mol375.70 kJ/mol
375.7
122200
👆🏻
18th Energy Level
3,300.00 kJ/mol3,757.00 kJ/mol
0
134810
👆🏻
19th Energy Level
1,086.50 kJ/mol375.70 kJ/mol
375.7
148700
👆🏻
20th Energy Level
880.00 kJ/mol375.00 kJ/mol
0
171200
👆🏻
21st Energy Level
1,086.00 kJ/mol375.70 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
350.00 kJ/mol375.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
1,120.00 kJ/mol375.70 kJ/mol
357.6
198800
👆🏻
24th Energy Level
540.90 kJ/mol375.70 kJ/mol
297.3
195200
👆🏻
25th Energy Level
610.00 kJ/mol375.70 kJ/mol
0
121900
👆🏻
26th Energy Level
587.40 kJ/mol375.70 kJ/mol
357.6
127700
👆🏻
27th Energy Level
880.00 kJ/mol375.70 kJ/mol
0
133800
👆🏻
28th Energy Level
840.00 kJ/mol375.70 kJ/mol
297.3
139800
👆🏻
29th Energy Level
867.80 kJ/mol375.70 kJ/mol
0
148100
👆🏻
30th Energy Level
0.00 kJ/mol375.70 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
3.00 g/amp-hr4.96 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
4.90 eV2.14 eV
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity
Chemical Stability, Corrosion, Ionization, Radioactive Isotopes, Solubility
Atomic Number
10855
3
117
👆🏻
Electron Configuration
[Rn] 5f14 6d6 7s2
[Xe] 6s1
Crystal Structure
Hexagonal Close Packed (HCP)
Body Centered Cubic (BCC)
Crystal Lattice
Atom
Number of Protons
10855
3
117
👆🏻
Number of Neutrons
15878
4
285
👆🏻
Number of Electrons
10855
3
117
👆🏻
Radius of an Atom
Atomic Radius
126.00 pm265.00 pm
0
348
👆🏻
Covalent Radius
134.00 pm244.00 pm
0
260
👆🏻
Van der Waals Radius
0.00 pm343.00 pm
0
348
👆🏻
Atomic Weight
269.00 amu132.91 amu
6.94
294
👆🏻
Atomic Volume
22.70 cm3/mol71.07 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
0.00 (-eV)8.62 (-eV)
0
392.42
👆🏻
Lattice Constant
-614.10 pm
0
891.25
👆🏻
Lattice Angles
-
π/2, π/2, π/2
Lattice C/A Ratio
1.311.87
0.423
1.9
👆🏻
Density
Density At Room Temperature
40.70 g/cm31.93 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
41.00 g/cm31.84 g/cm3
0.512
41
👆🏻
Tensile Strength
80.00 MPa15.00 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
40.00 GPa30.00 GPa
1.3
222
👆🏻
Bulk Modulus
40.00 GPa1.60 GPa
0
462
👆🏻
Young's Modulus
40.00 GPa1.70 GPa
0
528
👆🏻
Poisson Ratio
0.340.35
0.032
0.47
👆🏻
Other Mechanical Properties
-
Ductile
Magnetic Characteristics
Specific Gravity
41.001.87
0.53
4500
👆🏻
Magnetic Ordering
-
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
-
Semiconductor
Resistivity
41.00 nΩ·m205.00 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.00 106/cm Ω0.05 106/cm Ω
0
0.63
👆🏻
Electron Affinity
63.20 kJ/mol45.50 kJ/mol
0
222.8
👆🏻
Specific Heat
0.13 J/(kg K)0.24 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
25.92 J/mol·K32.21 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
0.00 W/m·K35.90 W/m·K
0
429
👆🏻
Critical Temperature
1,323.00 K1,938.00 K
26.3
3695
👆🏻
Thermal Expansion
21.20 µm/(m·K)97.00 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
126.00 kJ/mol65.90 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
-2.10 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
-78.20 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
57.20 J/mol.K85.20 J/mol.K
9.5
198.1
👆🏻