Symbol
✔
✘
✔
✘
Group Number
13
0
17
👆🏻
Period Number
67
2
7
👆🏻
Block
s block
f block
Element Family
Alkali
Actinide
CAS Number
744046210028145
7429905
54386242
👆🏻
Space Group Name
Im_ 3m
-
Space Group Number
229.00194.00
11
276
👆🏻
Interesting Facts
Cesium is the most alkaline metal and is used in atomic clocks.
- The most stable isotope of Nobelium metal is No-259.
- No-259 has a half-life of fifty-eight minutes.
Sources
Earth's crust, Found in Minerals, Mining, Ores of Minerals
Bombarding Curium-246 or Curium-249 with Carbon-12 Nuclei, Found in Minerals, Mining
History
Who Discovered
Robert Bunsen and Gustav Kirchhoff
Joint Institute for Nuclear Research
Discovery
In 1860
In 1966
Abundance
Abundance In Universe
0.00 %-
0
0.11
👆🏻
Abundance In Sun
0.00 %-
0
0.1
👆🏻
Abundance In Meteorites
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
- 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.
- Currently known uses of Nobelium metal are limited to research purpose only.
Industrial Uses
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic 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
0.05 p.p.m.0.00 p.p.m.
0
170000
👆🏻
Melting Point
28.50 °C827.00 °C
-38.83
3410
👆🏻
Boiling Point
678.40 °C2,600.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery Gold
-
Luster
-
Unknown Luster
Hardness
Mohs Hardness
0.20-
0.2
8.5
👆🏻
Brinell Hardness
0.14 MPa500.00 MPa
0.14
3490
👆🏻
Vickers Hardness
0.14 MPa500.00 MPa
0
3920
👆🏻
Speed of Sound
1,630.00 m/s1,100.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.931.30
0.155
3.41
👆🏻
Reflectivity
35.00 %61.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
✔
✘
✔
✘
Isotopes
Known Isotopes
3613
0
38
👆🏻
Electronegativity
Pauling Electronegativity
0.791.30
0
2.6
👆🏻
Sanderson Electronegativity
0.221.30
0.22
2.56
👆🏻
Allred Rochow Electronegativity
0.861.20
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
0.621.30
0.62
2.48
👆🏻
Allen Electronegativity
0.661.10
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
3.212.70
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
375.70 kJ/mol642.00 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
2,234.30 kJ/mol1,254.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
3,400.00 kJ/mol2,643.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
375.70 kJ/mol3,956.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
3,750.00 kJ/mol6,400.00 kJ/mol
392
97510
👆🏻
6th Energy Level
3,750.00 kJ/mol6,400.00 kJ/mol
1007
105800
👆🏻
7th Energy level
3,750.00 kJ/mol6,270.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
3,760.00 kJ/mol6,270.00 kJ/mol
730
125300
👆🏻
9th Energy Level
3,750.00 kJ/mol6,270.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
3,757.00 kJ/mol6,270.00 kJ/mol
392
144300
👆🏻
11th Energy Level
3,757.00 kJ/mol6,420.00 kJ/mol
392
169988
👆🏻
12th Energy Level
3,750.00 kJ/mol64,000.00 kJ/mol
0
189368
👆🏻
13th Energy Level
3,750.00 kJ/mol6,400.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
3,750.00 kJ/mol6,400.00 kJ/mol
380
86450
👆🏻
15th Energy Level
37,500.00 kJ/mol64,000.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
375.70 kJ/mol64,000.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
375.70 kJ/mol641.00 kJ/mol
375.7
122200
👆🏻
18th Energy Level
3,757.00 kJ/mol3,500.00 kJ/mol
0
134810
👆🏻
19th Energy Level
375.70 kJ/mol627.60 kJ/mol
375.7
148700
👆🏻
20th Energy Level
375.00 kJ/mol627.00 kJ/mol
0
171200
👆🏻
21st Energy Level
375.70 kJ/mol917.00 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
375.00 kJ/mol627.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
375.70 kJ/mol6,410.00 kJ/mol
357.6
198800
👆🏻
24th Energy Level
375.70 kJ/mol627.00 kJ/mol
297.3
195200
👆🏻
25th Energy Level
375.70 kJ/mol0.00 kJ/mol
0
121900
👆🏻
26th Energy Level
375.70 kJ/mol601.20 kJ/mol
357.6
127700
👆🏻
27th Energy Level
375.70 kJ/mol641.00 kJ/mol
0
133800
👆🏻
28th Energy Level
375.70 kJ/mol641.60 kJ/mol
297.3
139800
👆🏻
29th Energy Level
375.70 kJ/mol641.00 kJ/mol
0
148100
👆🏻
30th Energy Level
375.70 kJ/mol627.00 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
4.96 g/amp-hr4.83 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
2.14 eV4.90 eV
2.14
6
👆🏻
Other Chemical Properties
Chemical Stability, Corrosion, Ionization, Radioactive Isotopes, Solubility
Ionization, Radioactive Isotopes, Radioactivity
Atomic Number
55102
3
117
👆🏻
Electron Configuration
[Xe] 6s1
[Rn] 5f14 7s2
Crystal Structure
Body Centered Cubic (BCC)
Not Known
Crystal Lattice
Atom
Number of Protons
55102
3
117
👆🏻
Number of Neutrons
78157
4
285
👆🏻
Number of Electrons
55102
3
117
👆🏻
Radius of an Atom
Atomic Radius
265.00 pm176.00 pm
0
348
👆🏻
Covalent Radius
244.00 pm157.00 pm
0
260
👆🏻
Van der Waals Radius
343.00 pm246.00 pm
0
348
👆🏻
Atomic Weight
132.91 amu259.00 amu
6.94
294
👆🏻
Atomic Volume
71.07 cm3/mol19.80 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
8.62 (-eV)26.00 (-eV)
0
392.42
👆🏻
Lattice Constant
614.10 pm-
0
891.25
👆🏻
Lattice Angles
π/2, π/2, π/2
-
Lattice C/A Ratio
1.871.76
0.423
1.9
👆🏻
Density
Density At Room Temperature
1.93 g/cm39.90 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
1.84 g/cm39.90 g/cm3
0.512
41
👆🏻
Tensile Strength
15.00 MPa80.00 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
30.00 GPa27.00 GPa
1.3
222
👆🏻
Bulk Modulus
1.60 GPa8.70 GPa
0
462
👆🏻
Young's Modulus
1.70 GPa12.30 GPa
0
528
👆🏻
Poisson Ratio
0.350.30
0.032
0.47
👆🏻
Other Mechanical Properties
Ductile
-
Magnetic Characteristics
Specific Gravity
1.879.90
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
205.00 nΩ·m0.68 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.05 106/cm Ω0.00 106/cm Ω
0
0.63
👆🏻
Electron Affinity
45.50 kJ/mol50.00 kJ/mol
0
222.8
👆🏻
Specific Heat
0.24 J/(kg K)0.10 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
32.21 J/mol·K27.00 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
35.90 W/m·K0.10 W/m·K
0
429
👆🏻
Critical Temperature
1,938.00 K1,100.00 K
26.3
3695
👆🏻
Thermal Expansion
97.00 µm/(m·K)11.00 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
65.90 kJ/mol-
7.32
799.1
👆🏻
Enthalpy of Fusion
2.10 kJ/mol-
2.1
35.23
👆🏻
Enthalpy of Atomization
78.20 kJ/mol390.40 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
85.20 J/mol.K63.00 J/mol.K
9.5
198.1
👆🏻