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Thallium vs Fermium


Fermium vs Thallium


Periodic Table

Symbol
Tl  
Fm  

Group Number
13  
5
3  
15

Period Number
6  
7  

Block
p block  
f block  

Element Family
Post-​Transition  
Actinide  

CAS Number
7440280  
99+
7440724  
19

Space Group Name
P63/mmc  
-  

Space Group Number
194.00  
7
194.00  
7

Facts

Interesting Facts
  • Compounds of Thallium metal are highly Toxic.
  • Thallium metal is being suspected as a human carcinogen.
  
  • Fermium metal is highly radioactive in nature.
  • Fermium is synthetically produced metal.
  

Sources
Found As a By-product, Ores of metals, Ores of Minerals  
Bombarding Pu-239 with Neutrons  

History
  
  

Who Discovered
William Crookes  
Lawrence Berkeley National Laboratory  

Discovery
In 1861  
In 1952  

Abundance
  
  

Abundance In Universe
0.00 %  
33
0.00 %  
35

Abundance In Sun
0.00 %  
26
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
0.00 %  
34
-  

Abundance In Humans
0.00 %  
24
-  

Uses

Uses & Benefits
  • Thallium is a toxic metal and hence it has limited uses. Thallium metal is mostly used for producing photoelectric cells.
  • In thermometer’s mercury alloy has 8% of thallium, as it has a melting point lower than 20°C.
  
  • Currently known uses of Fermium metal are limited to research purpose only.
  

Industrial Uses
Chemical Industry  
-  

Medical Uses
Medical Research  
-  

Other Uses
Alloys  
-  

Biological Properties
  
  

Toxicity
Highly Toxic  
-  

Present in Human Body
Yes  
No  

In Blood
0.00 Blood/mg dm-3  
37
0.00 Blood/mg dm-3  
40

In Bone
0.00 p.p.m.  
38
0.00 p.p.m.  
99+

Physical

Melting Point
303.50 °C  
99+
1,527.00 °C  
26

Boiling Point
1,457.00 °C  
99+
0.00 °C  
99+

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery White  
-  

Luster
-  
-  

Hardness
  
  

Mohs Hardness
1.20  
21
6.00  
6

Brinell Hardness
26.50 MPa  
99+
500.00 MPa  
28

Vickers Hardness
120.00 MPa  
99+
600.00 MPa  
28

Speed of Sound
818.00 m/s  
99+
2,500.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.90  
18
1.30  
99+

Reflectivity
8.00 %  
37
59.00 %  
24

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
Tl  
Fm  

Isotopes
  
  

Known Isotopes
32  
7
18  
21

Electronegativity
  
  

Pauling Electronegativity
1.62  
22
1.30  
33

Sanderson Electronegativity
2.25  
6
1.30  
25

Allred Rochow Electronegativity
1.44  
18
1.20  
28

Mulliken-Jaffe Electronegativity
1.96  
11
1.30  
33

Allen Electronegativity
1.79  
16
1.30  
40

Electropositivity
  
  

Pauling Electropositivity
2.38  
33
2.70  
22

Ionization Energies
  
  

1st Energy Level
589.40 kJ/mol  
99+
627.00 kJ/mol  
99+

2nd Energy Level
1,971.00 kJ/mol  
14
1,225.00 kJ/mol  
99+

3rd Energy Level
2,878.00 kJ/mol  
32
2,363.00 kJ/mol  
99+

4th Energy Level
5,890.00 kJ/mol  
17
3,792.00 kJ/mol  
99+

5th Energy Level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
39

6th Energy Level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

7th Energy level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

8th Energy Level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

9th Energy Level
5,890.00 kJ/mol  
99+
7,040.00 kJ/mol  
33

10th Energy Level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

11th Energy Level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
99+

12th Energy Level
5,890.00 kJ/mol  
99+
62,700.00 kJ/mol  
10

13th Energy Level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
38

14th Energy Level
5,890.00 kJ/mol  
37
6,270.00 kJ/mol  
27

15th Energy Level
58,900.00 kJ/mol  
99+
62,700.00 kJ/mol  
38

16th Energy Level
58,900.00 kJ/mol  
38
62,700.00 kJ/mol  
28

17th Energy Level
589.40 kJ/mol  
99+
627.00 kJ/mol  
99+

18th Energy Level
5,890.00 kJ/mol  
99+
6,270.00 kJ/mol  
40

19th Energy Level
589.40 kJ/mol  
99+
994.80 kJ/mol  
21

20th Energy Level
589.00 kJ/mol  
99+
627.00 kJ/mol  
99+

21st Energy Level
589.40 kJ/mol  
99+
627.00 kJ/mol  
99+

22nd Energy Level
589.00 kJ/mol  
99+
345.00 kJ/mol  
99+

23rd Energy Level
589.40 kJ/mol  
99+
6,270.00 kJ/mol  
14

24th Energy Level
589.40 kJ/mol  
99+
627.60 kJ/mol  
38

25th Energy Level
589.40 kJ/mol  
99+
627.00 kJ/mol  
40

26th Energy Level
589.40 kJ/mol  
99+
627.60 kJ/mol  
39

27th Energy Level
589.40 kJ/mol  
99+
627.60 kJ/mol  
99+

28th Energy Level
589.40 kJ/mol  
99+
627.60 kJ/mol  
99+

29th Energy Level
589.40 kJ/mol  
99+
627.60 kJ/mol  
99+

30th Energy Level
589.40 kJ/mol  
99+
627.60 kJ/mol  
99+

Electrochemical Equivalent
7.63 g/amp-hr  
2
3.20 g/amp-hr  
15

Electron Work Function
3.84 eV  
39
4.47 eV  
21

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

Atomic

Atomic Number
81  
35
100  
18

Electron Configuration
[Xe] 4f14 5d10 6s2 6p1  
[Rn] 5f12 7s2  

Crystal Structure
Hexagonal Close Packed (HCP)  
Not Known  

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

Atom
  
  

Number of Protons
81  
35
100  
18

Number of Neutrons
123  
21
157  
8

Number of Electrons
81  
35
100  
18

Radius of an Atom
  
  

Atomic Radius
170.00 pm  
24
180.00 pm  
16

Covalent Radius
145.00 pm  
99+
180.00 pm  
23

Van der Waals Radius
196.00 pm  
37
245.00 pm  
13

Atomic Weight
204.38 amu  
31
257.00 amu  
15

Atomic Volume
17.20 cm3/mol  
99+
18.00 cm3/mol  
99+

Adjacent Atomic Numbers
  
  

Previous Element
Mercury
  

Next Element
Lead
  

Valence Electron Potential
9.60 (-eV)  
99+
0.00 (-eV)  
99+

Lattice Constant
345.66 pm  
99+
350.00 pm  
99+

Lattice Angles
π/2, π/2, 2 π/3  
-  

Lattice C/A Ratio
1.60  
23
1.63  
13

Mechanical

Density
  
  

Density At Room Temperature
11.85 g/cm3  
33
9.70 g/cm3  
99+

Density When Liquid (at m.p.)
11.22 g/cm3  
33
9.70 g/cm3  
99+

Tensile Strength
47.00 MPa  
39
0.10 MPa  
99+

Viscosity
0.00  
22
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
16.90 (Pa)  
5
0.00 (Pa)  
22

Vapor Pressure at 2000 K
0.00 (Pa)  
38
0.00 (Pa)  
30

Elasticity properties
  
  

Shear Modulus
2.80 GPa  
99+
30.00 GPa  
27

Bulk Modulus
43.00 GPa  
33
50.00 GPa  
24

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

Poisson Ratio
0.45  
2
0.35  
9

Other Mechanical Properties
Ductile, Sectile  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
11.85  
35
9.70  
99+

Magnetic Ordering
Diamagnetic  
-  

Permeability
0.00 H/m  
17
0.00 H/m  
16

Susceptibility
0.00  
28
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
-  

Resistivity
0.18 nΩ·m  
99+
7.90 nΩ·m  
99+

Electrical Conductivity
0.06 106/cm Ω  
37
0.00 106/cm Ω  
99+

Electron Affinity
19.20 kJ/mol  
38
0.00 kJ/mol  
99+

Thermal

Specific Heat
0.13 J/(kg K)  
40
0.10 J/(kg K)  
99+

Molar Heat Capacity
26.32 J/mol·K  
37
27.00 J/mol·K  
29

Thermal Conductivity
46.10 W/m·K  
33
0.00 W/m·K  
99+

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

Thermal Expansion
29.90 µm/(m·K)  
12
11.00 µm/(m·K)  
99+

Enthalpy
  
  

Enthalpy of Vaporization
162.10 kJ/mol  
99+
319.20 kJ/mol  
99+

Enthalpy of Fusion
4.27 kJ/mol  
99+
13.30 kJ/mol  
30

Enthalpy of Atomization
179.90 kJ/mol  
99+
-  

Standard Molar Entropy
64.20 J/mol.K  
20
50.00 J/mol.K  
99+

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