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Francium vs Chromium


Chromium vs Francium


Periodic Table

Symbol
Fr   
Cr   

Group Number
1   
17
6   
12

Period Number
7   
4   

Block
s block   
d block   

Element Family
Alkali   
Transition Metal   

CAS Number
7440735   
18
7440473   
39

Space Group Name
Not Available   
Im_ 3m   

Space Group Number
Not Available   
229.00   
1

Facts

Interesting Facts
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  
  • Chromium is highly reactive, hence it is not found free in nature.
  • Ores of Chromites mineral are the major source of Chromium metal.
  • Almost 90% leather tanning is done with the help of chromium.
  

Sources
Formed by Decay Process, Mining   
Found in Minerals, Mining, Ores of metals, Ores of Minerals   

History
  
  

Who Discovered
Marguerite Perey   
Louis Nicolas Vauquelin   

Discovery
In 1939   
In Between 1797 - 1798   

Abundance
  
  

Abundance In Universe
Not Available   
1.5 * 10-3 %   
7

Abundance In Sun
~-9999 %   
~0.002 %   
7

Abundance In Meteorites
Not Available   
0.30 %   
7

Abundance In Earth's Crust
Not Available   
0.01 %   
13

Abundance In Oceans
Not Available   
0.00 %   
16

Abundance In Humans
Not Available   
0.00 %   
16

Uses

Uses & Benefits
  • Francium has no known uses as it has a half life of only 22 minutes.
  
  • It is used to harden the steel and produces a stainless steel and other various alloys.
  • It is also used to give proper finish to polished mirrors. Its chromium plates are used in bathroom fittings.
  

Industrial Uses
NA   
Automobile Industry, Chemical Industry   

Medical Uses
NA   
NA   

Other Uses
NA   
Alloys   

Biological Properties
  
  

Toxicity
NA   
Highly Toxic   

Present in Human Body
No   
Yes   

In Blood
0.00 Blood/mg dm-3   
37
0.11 Blood/mg dm-3   
12

In Bone
0.00 p.p.m.   
36
0.33 p.p.m.   
21

Physical Properties

Melting Point
27.00 °C   
99+
1,857.00 °C   
14

Boiling Point
677.00 °C   
99+
2,672.00 °C   
39

Appearance
  
  

Physical State
Solid   
Solid   

Color
NA   
Silver   

Luster
NA   
Metallic   

Hardness
  
  

Mohs Hardness
Not Available   
8.50   
1

Brinell Hardness
Not Available   
687.00 MPa   
16

Vickers Hardness
Not Available   
1,060.00 MPa   
10

Speed of Sound
Not Available   
5,940.00 m/s   
5

Optical Properties
  
  

Allotropes
No   
No   

α Allotropes
Not Available   
Not Available   

β Allotropes
Not Available   
Not Available   

γ Allotropes
Not Available   
Not Available   

Chemical Properties

Chemical Formula
Fr   
Cr   

Isotopes
  
  

Known Isotopes
33   
6
21   
18

Electronegativity
  
  

Pauling Electronegativity
0.70   
99+
1.66   
18

Sanderson Electronegativity
Not Available   
1.66   
14

Allred Rochow Electronegativity
0.86   
99+
1.56   
10

Mulliken-Jaffe Electronegativity
0.68   
25
Not Available   

Allen Electronegativity
0.67   
99+
1.65   
19

Electropositivity
  
  

Pauling Electropositivity
3.30   
1
2.34   
36

Ionization Energies
  
  

1st Energy Level
380.00 kJ/mol   
99+
26,130.00 kJ/mol   
1

2nd Energy Level
Not Available   
28,750.00 kJ/mol   
1

3rd Energy Level
Not Available   
34,230.00 kJ/mol   
1

4th Energy Level
Not Available   
37,066.00 kJ/mol   
1

5th Energy Level
Not Available   
97,510.00 kJ/mol   
1

6th Energy Level
Not Available   
105,800.00 kJ/mol   
1

7th Energy level
Not Available   
114,300.00 kJ/mol   
1

8th Energy Level
Not Available   
125,300.00 kJ/mol   
1

9th Energy Level
Not Available   
134,700.00 kJ/mol   
1

10th Energy Level
Not Available   
144,300.00 kJ/mol   
1

11th Energy Level
Not Available   
26,130.00 kJ/mol   
12

12th Energy Level
Not Available   
28,750.00 kJ/mol   
13

13th Energy Level
Not Available   
34,230.00 kJ/mol   
10

14th Energy Level
Not Available   
37,066.00 kJ/mol   
12

15th Energy Level
Not Available   
97,510.00 kJ/mol   
1

16th Energy Level
Not Available   
105,800.00 kJ/mol   
2

17th Energy Level
Not Available   
114,300.00 kJ/mol   
3

18th Energy Level
Not Available   
125,300.00 kJ/mol   
4

19th Energy Level
Not Available   
134,700.00 kJ/mol   
5

20th Energy Level
Not Available   
144,300.00 kJ/mol   
7

21st Energy Level
Not Available   
157,700.00 kJ/mol   
7

22nd Energy Level
Not Available   
166,090.00 kJ/mol   
6

Electrochemical Equivalent
8.32 g/amp-hr   
1
0.32 g/amp-hr   
99+

Electron Work Function
Not Available   
4.50 eV   
14

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

Atomic Properties

Atomic Number
87   
31
24   
99+

Electron Configuration
[Rn] 7s1   
[Ar] 3d5 4s1   

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
24   
99+

Number of Neutrons
136   
17
28   
99+

Number of Electrons
87   
31
24   
99+

Radius of an Atom
  
  

Atomic Radius
Not Available   
128.00 pm   
99+

Covalent Radius
260.00 pm   
1
139.00 pm   
99+

Van der Waals Radius
348.00 pm   
1
200.00 pm   
28

Atomic Weight
223.00 amu   
27
52.00 amu   
99+

Atomic Volume
Not Available   
7.23 cm3/mol   
99+

Adjacent Atomic Numbers
  
  

Previous Element
Polonium
  
Vanadium
  

Next Element
Radium
  
Manganese
  

Valence Electron Potential
8.00 (-eV)   
99+
170.00 (-eV)   
4

Lattice Constant
Not Available   
291.00 pm   
99+

Lattice Angles
NA   
π/2, π/2, π/2   

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
1.87 g/cm3   
99+
7.19 g/cm3   
99+

Density When Liquid (at m.p.)
Not Available   
6.30 g/cm3   
40

Tensile Strength
Not Available   
689.00 MPa   
7

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
Not Available   
0.00 (Pa)   
24

Vapor Pressure at 2000 K
Not Available   
774.00 (Pa)   
1

Elasticity properties
  
  

Shear Modulus
Not Available   
115.00 GPa   
9

Bulk Modulus
Not Available   
160.00 GPa   
11

Young's Modulus
Not Available   
279.00 GPa   
8

Poisson Ratio
Not Available   
0.21   
32

Other Mechanical Properties
NA   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
Not Available   
7.19   
99+

Magnetic Ordering
Paramagnetic   
Antiferromagnetic   

Electrical Properties
  
  

Electrical Property
Poor Conductor   
NA   

Resistivity
3.00 nΩ·m   
99+
125.00 nΩ·m   
27

Electrical Conductivity
0.03 106/cm Ω   
40
0.08 106/cm Ω   
25

Electron Affinity
Not Available   
64.30 kJ/mol   
15

Thermal Properties

Specific Heat
Not Available   
0.45 J/(kg K)   
12

Molar Heat Capacity
Not Available   
23.35 J/mol·K   
99+

Thermal Conductivity
15.00 W/m·K   
99+
93.90 W/m·K   
17

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
Not Available   
4.90 µm/(m·K)   
99+

Enthalpy
  
  

Enthalpy of Vaporization
Not Available   
348.80 kJ/mol   
24

Enthalpy of Fusion
Not Available   
15.31 kJ/mol   
20

Enthalpy of Atomization
71.00 kJ/mol   
99+
397.50 kJ/mol   
21

Standard Molar Entropy
Not Available   
23.80 J/mol.K   
99+

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