Home
 Compare Metals

Francium vs Cesium

Francium
Cesium
Cesium vs Francium


Periodic Table
Symbol
Fr  
Cs  
Group Number
1  
17
1  
17
Period Number
7  
6  
Block
s block  
s block  
Element Family
Alkali  
Alkali  
CAS Number
7440735  
18
7440462  
40
Space Group Name
-  
Im_ 3m  
Space Group Number
225.00  
3
229.00  
2
Facts
Interesting Facts
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  
Cesium is the most alkaline metal and is used in atomic clocks.  
Sources
Formed by Decay Process, Mining  
Earth's crust, Found in Minerals, Mining, Ores of Minerals  
History
  
  
Who Discovered
Marguerite Perey  
Robert Bunsen and Gustav Kirchhoff  
Discovery
In 1939  
In 1860  
Abundance
  
  
Abundance In Universe
0.00 %  
40
0.00 %  
25
Abundance In Sun
0.00 %  
30
0.00 %  
20
Abundance In Meteorites
0.00 %  
99+
0.00 %  
38
Abundance In Earth's Crust
0.00 %  
99+
0.00 %  
35
Abundance In Oceans
-  
0.00 %  
17
Abundance In Humans
0.00 %  
24
0.00 %  
20
Uses
Uses & Benefits
  • Francium has no known uses as it has a half life of only 22 minutes.
  
  • 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
-  
Alloys  
Biological Properties
  
  
Toxicity
-  
Mildly Toxic  
Present in Human Body
No  
Yes  
In Blood
0.00 Blood/mg dm-3  
40
0.00 Blood/mg dm-3  
28
In Bone
0.00 p.p.m.  
99+
0.05 p.p.m.  
31
Physical
Melting Point
27.00 °C  
99+
28.50 °C  
99+
Boiling Point
677.00 °C  
99+
678.40 °C  
99+
Appearance
  
  
Physical State
Solid  
Solid  
Color
-  
Silvery Gold  
Luster
-  
-  
Hardness
  
  
Mohs Hardness
0.20  
27
0.20  
27
Brinell Hardness
119.00 MPa  
99+
0.14 MPa  
99+
Vickers Hardness
300.00 MPa  
99+
0.14 MPa  
99+
Speed of Sound
2,440.00 m/s  
99+
1,630.00 m/s  
99+
Optical Properties
  
  
Refractive Index
1.70  
27
1.93  
17
Reflectivity
72.00 %  
11
35.00 %  
34
Allotropes
No  
No  
α Allotropes
-  
-  
β Allotropes
-  
-  
γ Allotropes
-  
-  
Chemical
Chemical Formula
Fr  
Cs  
Isotopes
  
  
Known Isotopes
33  
6
36  
3
Electronegativity
  
  
Pauling Electronegativity
0.70  
99+
0.79  
99+
Sanderson Electronegativity
0.70  
99+
0.22  
99+
Allred Rochow Electronegativity
0.86  
99+
0.86  
99+
Mulliken-Jaffe Electronegativity
0.68  
99+
0.62  
99+
Allen Electronegativity
0.67  
99+
0.66  
99+
Electropositivity
  
  
Pauling Electropositivity
3.30  
1
3.21  
2
Ionization Energies
  
  
1st Energy Level
380.00 kJ/mol  
99+
375.70 kJ/mol  
99+
2nd Energy Level
392.80 kJ/mol  
99+
2,234.30 kJ/mol  
8
3rd Energy Level
392.80 kJ/mol  
99+
3,400.00 kJ/mol  
16
4th Energy Level
392.80 kJ/mol  
99+
375.70 kJ/mol  
99+
5th Energy Level
392.00 kJ/mol  
99+
3,750.00 kJ/mol  
99+
6th Energy Level
3,920.00 kJ/mol  
99+
3,750.00 kJ/mol  
99+
7th Energy level
3,920.00 kJ/mol  
99+
3,750.00 kJ/mol  
99+
8th Energy Level
3,920.00 kJ/mol  
99+
3,760.00 kJ/mol  
99+
9th Energy Level
3,920.00 kJ/mol  
99+
3,750.00 kJ/mol  
99+
10th Energy Level
392.00 kJ/mol  
99+
3,757.00 kJ/mol  
99+
11th Energy Level
392.00 kJ/mol  
99+
3,757.00 kJ/mol  
99+
12th Energy Level
38,000.00 kJ/mol  
23
3,750.00 kJ/mol  
99+
13th Energy Level
3,920.00 kJ/mol  
99+
3,750.00 kJ/mol  
99+
14th Energy Level
380.00 kJ/mol  
99+
3,750.00 kJ/mol  
99+
15th Energy Level
67,700.00 kJ/mol  
32
37,500.00 kJ/mol  
99+
16th Energy Level
39,200.00 kJ/mol  
99+
375.70 kJ/mol  
99+
17th Energy Level
392.00 kJ/mol  
99+
375.70 kJ/mol  
99+
18th Energy Level
3,920.00 kJ/mol  
99+
3,757.00 kJ/mol  
99+
19th Energy Level
392.80 kJ/mol  
99+
375.70 kJ/mol  
99+
20th Energy Level
392.00 kJ/mol  
99+
375.00 kJ/mol  
99+
21st Energy Level
392.00 kJ/mol  
99+
375.70 kJ/mol  
99+
22nd Energy Level
392.00 kJ/mol  
99+
375.00 kJ/mol  
99+
23rd Energy Level
392.80 kJ/mol  
99+
375.70 kJ/mol  
99+
24th Energy Level
392.00 kJ/mol  
99+
375.70 kJ/mol  
99+
25th Energy Level
392.00 kJ/mol  
99+
375.70 kJ/mol  
99+
26th Energy Level
392.80 kJ/mol  
99+
375.70 kJ/mol  
99+
27th Energy Level
392.00 kJ/mol  
99+
375.70 kJ/mol  
99+
28th Energy Level
380.00 kJ/mol  
99+
375.70 kJ/mol  
99+
29th Energy Level
392.00 kJ/mol  
99+
375.70 kJ/mol  
99+
30th Energy Level
677.00 kJ/mol  
31
375.70 kJ/mol  
99+
Electrochemical Equivalent
8.32 g/amp-hr  
1
4.96 g/amp-hr  
3
Electron Work Function
4.07 eV  
33
2.14 eV  
99+
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility  
Chemical Stability, Corrosion, Ionization, Radioactive Isotopes, Solubility  
Atomic
Atomic Number
87  
31
55  
99+
Electron Configuration
[Rn] 7s1  
[Xe] 6s1  
Crystal Structure
Body Centered Cubic (BCC)  
Body Centered Cubic (BCC)  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100  
BCC-Crystal-Structure-.jpg#100  
Atom
  
  
Number of Protons
87  
31
55  
99+
Number of Neutrons
136  
18
78  
99+
Number of Electrons
87  
31
55  
99+
Radius of an Atom
  
  
Atomic Radius
348.00 pm  
1
265.00 pm  
2
Covalent Radius
260.00 pm  
1
244.00 pm  
2
Van der Waals Radius
348.00 pm  
1
343.00 pm  
2
Atomic Weight
223.00 amu  
27
132.91 amu  
99+
Atomic Volume
71.00 cm3/mol  
2
71.07 cm3/mol  
1
Adjacent Atomic Numbers
  
  
Previous Element
Polonium
  
Tin
  
Next Element
Radium
  
Barium
  
Valence Electron Potential
8.00 (-eV)  
99+
8.62 (-eV)  
99+
Lattice Constant
440.00 pm  
21
614.10 pm  
5
Lattice Angles
-  
π/2, π/2, π/2  
Lattice C/A Ratio
1.56  
99+
1.87  
3
Mechanical
Density
  
  
Density At Room Temperature
1.87 g/cm3  
99+
1.93 g/cm3  
99+
Density When Liquid (at m.p.)
1.87 g/cm3  
99+
1.84 g/cm3  
99+
Tensile Strength
50.00 MPa  
38
15.00 MPa  
99+
Viscosity
0.00  
25
0.00  
25
Vapor Pressure
  
  
Vapor Pressure at 1000 K
0.00 (Pa)  
37
0.00 (Pa)  
22
Vapor Pressure at 2000 K
0.00 (Pa)  
24
0.00 (Pa)  
30
Elasticity properties
  
  
Shear Modulus
3.60 GPa  
99+
30.00 GPa  
27
Bulk Modulus
6.00 GPa  
99+
1.60 GPa  
99+
Young's Modulus
0.00 GPa  
99+
1.70 GPa  
99+
Poisson Ratio
0.44  
3
0.35  
9
Other Mechanical Properties
-  
Ductile  
Magnetic
Magnetic Characteristics
  
  
Specific Gravity
0.87  
99+
1.87  
99+
Magnetic Ordering
Paramagnetic  
Paramagnetic  
Permeability
0.00 H/m  
13
0.00 H/m  
17
Susceptibility
0.00  
24
0.00  
24
Electrical Properties
  
  
Electrical Property
Poor Conductor  
Semiconductor  
Resistivity
3.00 nΩ·m  
99+
205.00 nΩ·m  
17
Electrical Conductivity
0.03 106/cm Ω  
99+
0.05 106/cm Ω  
40
Electron Affinity
0.70 kJ/mol  
99+
45.50 kJ/mol  
30
Thermal
Specific Heat
0.15 J/(kg K)  
37
0.24 J/(kg K)  
23
Molar Heat Capacity
27.00 J/mol·K  
29
32.21 J/mol·K  
6
Thermal Conductivity
15.00 W/m·K  
99+
35.90 W/m·K  
37
Critical Temperature
300.00 K  
99+
1,938.00 K  
22
Thermal Expansion
18.90 µm/(m·K)  
25
97.00 µm/(m·K)  
1
Enthalpy
  
  
Enthalpy of Vaporization
67.00 kJ/mol  
99+
65.90 kJ/mol  
99+
Enthalpy of Fusion
2.30 kJ/mol  
99+
2.10 kJ/mol  
99+
Enthalpy of Atomization
71.00 kJ/mol  
99+
78.20 kJ/mol  
99+
Standard Molar Entropy
42.00 J/mol.K  
99+
85.20 J/mol.K  
3
Periodic Table >>
<< All

Compare Alkali Metals

Alkali Metals

Alkali Metals

» More Alkali Metals

Compare Alkali Metals

» More Compare Alkali Metals
Home | About | Contact | Disclaimer | Terms of use
© A softusvista inc. venture!