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Francium vs Bohrium


Bohrium vs Francium


Periodic Table

Symbol
Fr  
Bh  

Group Number
1  
17
7  
11

Period Number
7  
7  

Block
s block  
d block  

Element Family
Alkali  
Transition Metal  

CAS Number
7440735  
18
54037148  
12

Space Group Name
-  
-  

Space Group Number
225.00  
3
276.00  
1

Facts

Interesting Facts
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  
  • Bohrium metal is also known as Unnilseptium (Uns) and Nielsbohrium (Ns).
  

Sources
Formed by Decay Process, Mining  
Found in Minerals, Mining, Synthetically Produced  

History
  
  

Who Discovered
Marguerite Perey  
Gesellschaft für Schwerionenforschung  

Discovery
In 1939  
In 1981  

Abundance
  
  

Abundance In Universe
0.00 %  
40
0.00 %  
37

Abundance In Sun
0.00 %  
30
-  

Abundance In Meteorites
0.00 %  
99+
0.00 %  
99+

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

Abundance In Oceans
-  
-  

Abundance In Humans
0.00 %  
24
-  

Uses

Uses & Benefits
  • Francium has no known uses as it has a half life of only 22 minutes.
  
  • Currently known uses of Bohrium metal are limited to research purpose only.
  

Industrial Uses
-  
-  

Medical Uses
-  
-  

Other Uses
-  
Research Purposes  

Biological Properties
  
  

Toxicity
-  
-  

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
27.00 °C  
99+
-  

Boiling Point
677.00 °C  
99+
0.00 °C  
99+

Appearance
  
  

Physical State
Solid  
Solid  

Color
-  
-  

Luster
-  
Unknown Luster  

Hardness
  
  

Mohs Hardness
0.20  
27
7.00  
3

Brinell Hardness
119.00 MPa  
99+
270.00 MPa  
99+

Vickers Hardness
300.00 MPa  
99+
2,700.00 MPa  
4

Speed of Sound
2,440.00 m/s  
99+
2,680.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.70  
27
1.50  
36

Reflectivity
72.00 %  
11
59.00 %  
24

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Fr  
Bh  

Isotopes
  
  

Known Isotopes
33  
6
5  
32

Electronegativity
  
  

Pauling Electronegativity
0.70  
99+
2.00  
8

Sanderson Electronegativity
0.70  
99+
1.30  
25

Allred Rochow Electronegativity
0.86  
99+
1.30  
25

Mulliken-Jaffe Electronegativity
0.68  
99+
1.30  
33

Allen Electronegativity
0.67  
99+
2.00  
6

Electropositivity
  
  

Pauling Electropositivity
3.30  
1
2.00  
99+

Ionization Energies
  
  

1st Energy Level
380.00 kJ/mol  
99+
742.90 kJ/mol  
23

2nd Energy Level
392.80 kJ/mol  
99+
1,688.50 kJ/mol  
31

3rd Energy Level
392.80 kJ/mol  
99+
2,566.50 kJ/mol  
99+

4th Energy Level
392.80 kJ/mol  
99+
3,598.90 kJ/mol  
99+

5th Energy Level
392.00 kJ/mol  
99+
4,727.80 kJ/mol  
99+

6th Energy Level
3,920.00 kJ/mol  
99+
5,991.70 kJ/mol  
99+

7th Energy level
3,920.00 kJ/mol  
99+
7,226.80 kJ/mol  
34

8th Energy Level
3,920.00 kJ/mol  
99+
7,100.00 kJ/mol  
33

9th Energy Level
3,920.00 kJ/mol  
99+
5,800.00 kJ/mol  
99+

10th Energy Level
392.00 kJ/mol  
99+
7,100.00 kJ/mol  
35

11th Energy Level
392.00 kJ/mol  
99+
8,200.00 kJ/mol  
25

12th Energy Level
38,000.00 kJ/mol  
23
82,700.00 kJ/mol  
4

13th Energy Level
3,920.00 kJ/mol  
99+
7,100.00 kJ/mol  
29

14th Energy Level
380.00 kJ/mol  
99+
8,200.00 kJ/mol  
17

15th Energy Level
67,700.00 kJ/mol  
32
82,000.00 kJ/mol  
14

16th Energy Level
39,200.00 kJ/mol  
99+
71,100.00 kJ/mol  
20

17th Energy Level
392.00 kJ/mol  
99+
820.00 kJ/mol  
31

18th Energy Level
3,920.00 kJ/mol  
99+
8,200.00 kJ/mol  
20

19th Energy Level
392.80 kJ/mol  
99+
820.80 kJ/mol  
28

20th Energy Level
392.00 kJ/mol  
99+
820.00 kJ/mol  
21

21st Energy Level
392.00 kJ/mol  
99+
8,200.00 kJ/mol  
11

22nd Energy Level
392.00 kJ/mol  
99+
820.00 kJ/mol  
16

23rd Energy Level
392.80 kJ/mol  
99+
8,200.00 kJ/mol  
8

24th Energy Level
392.00 kJ/mol  
99+
820.00 kJ/mol  
12

25th Energy Level
392.00 kJ/mol  
99+
820.00 kJ/mol  
10

26th Energy Level
392.80 kJ/mol  
99+
820.00 kJ/mol  
10

27th Energy Level
392.00 kJ/mol  
99+
820.00 kJ/mol  
9

28th Energy Level
380.00 kJ/mol  
99+
820.00 kJ/mol  
15

29th Energy Level
392.00 kJ/mol  
99+
820.00 kJ/mol  
14

30th Energy Level
677.00 kJ/mol  
31
820.00 kJ/mol  
10

Electrochemical Equivalent
8.32 g/amp-hr  
1
3.00 g/amp-hr  
21

Electron Work Function
4.07 eV  
33
4.90 eV  
12

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

Atomic

Atomic Number
87  
31
107  
11

Electron Configuration
[Rn] 7s1  
[Rn] 5f14 6d5 7s2  

Crystal Structure
Body Centered Cubic (BCC)  
Hexagonal Close Packed (HCP)  

Crystal Lattice
BCC-Crystal-Structure-.jpg#100  
BCC-Crystal-Structure-.jpg#100  

Atom
  
  

Number of Protons
87  
31
107  
11

Number of Neutrons
136  
18
155  
9

Number of Electrons
87  
31
107  
11

Radius of an Atom
  
  

Atomic Radius
348.00 pm  
1
128.00 pm  
99+

Covalent Radius
260.00 pm  
1
141.00 pm  
99+

Van der Waals Radius
348.00 pm  
1
0.00 pm  
99+

Atomic Weight
223.00 amu  
27
270.00 amu  
8

Atomic Volume
71.00 cm3/mol  
2
23.70 cm3/mol  
14

Adjacent Atomic Numbers
  
  

Previous Element
Polonium
  

Next Element
Radium
  
Hassium
  

Valence Electron Potential
8.00 (-eV)  
99+
27.20 (-eV)  
99+

Lattice Constant
440.00 pm  
21
-  

Lattice Angles
-  
-  

Lattice C/A Ratio
1.56  
99+
1.57  
99+

Mechanical

Density
  
  

Density At Room Temperature
1.87 g/cm3  
99+
37.10 g/cm3  
3

Density When Liquid (at m.p.)
1.87 g/cm3  
99+
37.10 g/cm3  
3

Tensile Strength
50.00 MPa  
38
152.00 MPa  
24

Viscosity
0.00  
25
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
37
0.00 (Pa)  
37

Vapor Pressure at 2000 K
0.00 (Pa)  
24
0.00 (Pa)  
37

Elasticity properties
  
  

Shear Modulus
3.60 GPa  
99+
28.00 GPa  
32

Bulk Modulus
6.00 GPa  
99+
37.00 GPa  
99+

Young's Modulus
0.00 GPa  
99+
0.00 GPa  
99+

Poisson Ratio
0.44  
3
0.35  
9

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
0.87  
99+
37.00  
5

Magnetic Ordering
Paramagnetic  
-  

Permeability
0.00 H/m  
13
0.00 H/m  
11

Susceptibility
0.00  
24
0.00  
24

Electrical Properties
  
  

Electrical Property
Poor Conductor  
-  

Resistivity
3.00 nΩ·m  
99+
6.50 nΩ·m  
99+

Electrical Conductivity
0.03 106/cm Ω  
99+
0.00 106/cm Ω  
99+

Electron Affinity
0.70 kJ/mol  
99+
-  

Thermal

Specific Heat
0.15 J/(kg K)  
37
0.10 J/(kg K)  
99+

Molar Heat Capacity
27.00 J/mol·K  
29
37.10 J/mol·K  
2

Thermal Conductivity
15.00 W/m·K  
99+
37.00 W/m·K  
36

Critical Temperature
300.00 K  
99+
1,323.00 K  
99+

Thermal Expansion
18.90 µm/(m·K)  
25
14.30 µm/(m·K)  
28

Enthalpy
  
  

Enthalpy of Vaporization
67.00 kJ/mol  
99+
270.50 kJ/mol  
99+

Enthalpy of Fusion
2.30 kJ/mol  
99+
-  

Enthalpy of Atomization
71.00 kJ/mol  
99+
-  

Standard Molar Entropy
42.00 J/mol.K  
99+
57.00 J/mol.K  
30

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