Home
Compare Metals


Mendelevium vs Francium


Francium vs Mendelevium


Periodic Table

Symbol
Md  
Fr  

Group Number
3  
15
1  
17

Period Number
7  
7  

Block
f block  
s block  

Element Family
Actinide  
Alkali  

CAS Number
7440111  
99+
7440735  
18

Space Group Name
-  
-  

Space Group Number
194.00  
7
225.00  
3

Facts

Interesting Facts
  • Mendelevium metal is synthetically produced metal.
  • Mendelevium metal has been produced in only trace amount.
  
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  

Sources
Bombarding Einsteinium with Helium Ions  
Formed by Decay Process, Mining  

History
  
  

Who Discovered
Lawrence Berkeley National Laboratory  
Marguerite Perey  

Discovery
In 1955  
In 1939  

Abundance
  
  

Abundance In Universe
0.00 %  
40
0.00 %  
40

Abundance In Sun
-  
0.00 %  
30

Abundance In Meteorites
0.00 %  
99+
0.00 %  
99+

Abundance In Earth's Crust
-  
0.00 %  
99+

Abundance In Oceans
-  
-  

Abundance In Humans
0.00 %  
24
0.00 %  
24

Uses

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

Industrial Uses
-  
-  

Medical Uses
-  
-  

Other Uses
-  
-  

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
827.00 °C  
99+
27.00 °C  
99+

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

Appearance
  
  

Physical State
Solid  
Solid  

Color
-  
-  

Luster
Metallic  
-  

Hardness
  
  

Mohs Hardness
-  
0.20  
27

Brinell Hardness
350.00 MPa  
36
119.00 MPa  
99+

Vickers Hardness
0.00 MPa  
99+
300.00 MPa  
99+

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

Optical Properties
  
  

Refractive Index
1.30  
99+
1.70  
27

Reflectivity
66.00 %  
17
72.00 %  
11

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Md  
Fr  

Isotopes
  
  

Known Isotopes
16  
23
33  
6

Electronegativity
  
  

Pauling Electronegativity
1.30  
33
0.70  
99+

Sanderson Electronegativity
1.30  
25
0.70  
99+

Allred Rochow Electronegativity
1.20  
28
0.86  
99+

Mulliken-Jaffe Electronegativity
1.30  
33
0.68  
99+

Allen Electronegativity
1.30  
40
0.67  
99+

Electropositivity
  
  

Pauling Electropositivity
2.70  
22
3.30  
1

Ionization Energies
  
  

1st Energy Level
635.00 kJ/mol  
99+
380.00 kJ/mol  
99+

2nd Energy Level
1,235.00 kJ/mol  
99+
392.80 kJ/mol  
99+

3rd Energy Level
2,470.00 kJ/mol  
99+
392.80 kJ/mol  
99+

4th Energy Level
3,840.00 kJ/mol  
99+
392.80 kJ/mol  
99+

5th Energy Level
6,350.00 kJ/mol  
36
392.00 kJ/mol  
99+

6th Energy Level
6,350.00 kJ/mol  
99+
3,920.00 kJ/mol  
99+

7th Energy level
6,350.00 kJ/mol  
99+
3,920.00 kJ/mol  
99+

8th Energy Level
6,350.00 kJ/mol  
99+
3,920.00 kJ/mol  
99+

9th Energy Level
6,350.00 kJ/mol  
99+
3,920.00 kJ/mol  
99+

10th Energy Level
6,350.00 kJ/mol  
99+
392.00 kJ/mol  
99+

11th Energy Level
6,400.00 kJ/mol  
99+
392.00 kJ/mol  
99+

12th Energy Level
60,100.00 kJ/mol  
16
38,000.00 kJ/mol  
23

13th Energy Level
6,350.00 kJ/mol  
37
3,920.00 kJ/mol  
99+

14th Energy Level
1,150.00 kJ/mol  
99+
380.00 kJ/mol  
99+

15th Energy Level
63,500.00 kJ/mol  
37
67,700.00 kJ/mol  
32

16th Energy Level
635.00 kJ/mol  
99+
39,200.00 kJ/mol  
99+

17th Energy Level
1,107.00 kJ/mol  
21
392.00 kJ/mol  
99+

18th Energy Level
6,350.00 kJ/mol  
39
3,920.00 kJ/mol  
99+

19th Energy Level
635.00 kJ/mol  
99+
392.80 kJ/mol  
99+

20th Energy Level
635.00 kJ/mol  
40
392.00 kJ/mol  
99+

21st Energy Level
6,350.00 kJ/mol  
13
392.00 kJ/mol  
99+

22nd Energy Level
635.00 kJ/mol  
34
392.00 kJ/mol  
99+

23rd Energy Level
6,350.00 kJ/mol  
13
392.80 kJ/mol  
99+

24th Energy Level
635.00 kJ/mol  
36
392.00 kJ/mol  
99+

25th Energy Level
635.00 kJ/mol  
38
392.00 kJ/mol  
99+

26th Energy Level
635.00 kJ/mol  
37
392.80 kJ/mol  
99+

27th Energy Level
635.00 kJ/mol  
39
392.00 kJ/mol  
99+

28th Energy Level
635.00 kJ/mol  
99+
380.00 kJ/mol  
99+

29th Energy Level
635.00 kJ/mol  
99+
392.00 kJ/mol  
99+

30th Energy Level
635.00 kJ/mol  
40
677.00 kJ/mol  
31

Electrochemical Equivalent
3.21 g/amp-hr  
13
8.32 g/amp-hr  
1

Electron Work Function
3.89 eV  
37
4.07 eV  
33

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

Atomic

Atomic Number
101  
17
87  
31

Electron Configuration
[Rn] 5f13 7s2  
[Rn] 7s1  

Crystal Structure
Not Known  
Body Centered Cubic (BCC)  

Crystal Lattice
Unknown-Crystal-Structure-of-Mendelevium.jpg#100  
BCC-Crystal-Structure-.jpg#100  

Atom
  
  

Number of Protons
101  
17
87  
31

Number of Neutrons
157  
8
136  
18

Number of Electrons
101  
17
87  
31

Radius of an Atom
  
  

Atomic Radius
175.00 pm  
21
348.00 pm  
1

Covalent Radius
175.00 pm  
25
260.00 pm  
1

Van der Waals Radius
246.00 pm  
12
348.00 pm  
1

Atomic Weight
258.00 amu  
14
223.00 amu  
27

Atomic Volume
19.90 cm3/mol  
32
71.00 cm3/mol  
2

Adjacent Atomic Numbers
  
  

Previous Element
Fermium
  
Polonium
  

Next Element
Nobelium
  
Radium
  

Valence Electron Potential
63.70 (-eV)  
23
8.00 (-eV)  
99+

Lattice Constant
-  
440.00 pm  
21

Lattice Angles
-  
-  

Lattice C/A Ratio
1.58  
36
1.56  
99+

Mechanical

Density
  
  

Density At Room Temperature
10.30 g/cm3  
38
1.87 g/cm3  
99+

Density When Liquid (at m.p.)
10.30 g/cm3  
39
1.87 g/cm3  
99+

Tensile Strength
80.00 MPa  
29
50.00 MPa  
38

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)  
37
0.00 (Pa)  
24

Elasticity properties
  
  

Shear Modulus
32.00 GPa  
24
3.60 GPa  
99+

Bulk Modulus
0.00 GPa  
99+
6.00 GPa  
99+

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

Poisson Ratio
0.30  
14
0.44  
3

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
13.50  
29
0.87  
99+

Magnetic Ordering
-  
Paramagnetic  

Permeability
0.00 H/m  
11
0.00 H/m  
13

Susceptibility
0.00  
24
0.00  
24

Electrical Properties
  
  

Electrical Property
-  
Poor Conductor  

Resistivity
0.63 nΩ·m  
99+
3.00 nΩ·m  
99+

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

Electron Affinity
50.00 kJ/mol  
26
0.70 kJ/mol  
99+

Thermal

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

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

Thermal Conductivity
0.00 W/m·K  
99+
15.00 W/m·K  
99+

Critical Temperature
1,100.00 K  
99+
300.00 K  
99+

Thermal Expansion
11.60 µm/(m·K)  
99+
18.90 µm/(m·K)  
25

Enthalpy
  
  

Enthalpy of Vaporization
380.50 kJ/mol  
26
67.00 kJ/mol  
99+

Enthalpy of Fusion
-  
2.30 kJ/mol  
99+

Enthalpy of Atomization
410.80 kJ/mol  
25
71.00 kJ/mol  
99+

Standard Molar Entropy
37.40 J/mol.K  
99+
42.00 J/mol.K  
99+

Periodic Table >>
<< All

Compare Actinide Series

Actinide Series

Actinide Series

» More Actinide Series

Compare Actinide Series

» More Compare Actinide Series