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Potassium vs Francium


Francium vs Potassium


Periodic Table

Symbol
K  
Fr  

Group Number
1  
17
1  
17

Period Number
4  
7  

Block
s block  
s block  

Element Family
Alkali  
Alkali  

CAS Number
7440097  
99+
7440735  
18

Space Group Name
Im_ 3m  
-  

Space Group Number
229.00  
2
225.00  
3

Facts

Interesting Facts
  • In the list of most abundant element Potassium is ranked 7th.
  • Potassium can easily be sliced (chopped) down using knife.
  
  • 223 Francium has the longest half life at 21.8.
  • Francium metal is produced by alpha decay in 227Actinium 227.
  

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

History
  
  

Who Discovered
Humphry Davy  
Marguerite Perey  

Discovery
In 1807  
In 1939  

Abundance
  
  

Abundance In Universe
0.00 %  
10
0.00 %  
40

Abundance In Sun
0.00 %  
9
0.00 %  
30

Abundance In Meteorites
0.07 %  
9
0.00 %  
99+

Abundance In Earth's Crust
1.50 %  
6
0.00 %  
99+

Abundance In Oceans
0.04 %  
3
-  

Abundance In Humans
0.20 %  
3
0.00 %  
24

Uses

Uses & Benefits
  • Potassium’s compounds are in high demand for their application in Fertilizer manufacturing.
  • Potassium carbonate is used in glass manufacturing and Potassium carbonate in manufacturing detergent and body wash.
  
  • Francium has no known uses as it has a half life of only 22 minutes.
  

Industrial Uses
Ammunition Industry, Chemical Industry  
-  

Medical Uses
Pharmaceutical Industry  
-  

Other Uses
-  
-  

Biological Properties
  
  

Toxicity
Toxic  
-  

Present in Human Body
Yes  
No  

In Blood
1,620.00 Blood/mg dm-3  
2
0.00 Blood/mg dm-3  
40

In Bone
2,100.00 p.p.m.  
3
0.00 p.p.m.  
99+

Physical

Melting Point
63.65 °C  
99+
27.00 °C  
99+

Boiling Point
774.00 °C  
99+
677.00 °C  
99+

Appearance
  
  

Physical State
Solid  
Solid  

Color
Silvery Gray  
-  

Luster
-  
-  

Hardness
  
  

Mohs Hardness
0.40  
25
0.20  
27

Brinell Hardness
0.36 MPa  
99+
119.00 MPa  
99+

Vickers Hardness
100.00 MPa  
99+
300.00 MPa  
99+

Speed of Sound
2,000.00 m/s  
99+
2,440.00 m/s  
99+

Optical Properties
  
  

Refractive Index
1.33  
99+
1.70  
27

Reflectivity
72.00 %  
11
72.00 %  
11

Allotropes
No  
No  

α Allotropes
-  
-  

β Allotropes
-  
-  

γ Allotropes
-  
-  

Chemical

Chemical Formula
K  
Fr  

Isotopes
  
  

Known Isotopes
20  
19
33  
6

Electronegativity
  
  

Pauling Electronegativity
0.82  
99+
0.70  
99+

Sanderson Electronegativity
0.45  
99+
0.70  
99+

Allred Rochow Electronegativity
0.91  
40
0.86  
99+

Mulliken-Jaffe Electronegativity
0.73  
99+
0.68  
99+

Allen Electronegativity
0.73  
99+
0.67  
99+

Electropositivity
  
  

Pauling Electropositivity
3.18  
3
3.30  
1

Ionization Energies
  
  

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

2nd Energy Level
3,052.00 kJ/mol  
5
392.80 kJ/mol  
99+

3rd Energy Level
4,420.00 kJ/mol  
8
392.80 kJ/mol  
99+

4th Energy Level
5,877.00 kJ/mol  
18
392.80 kJ/mol  
99+

5th Energy Level
7,975.00 kJ/mol  
14
392.00 kJ/mol  
99+

6th Energy Level
9,590.00 kJ/mol  
19
3,920.00 kJ/mol  
99+

7th Energy level
11,343.00 kJ/mol  
17
3,920.00 kJ/mol  
99+

8th Energy Level
14,944.00 kJ/mol  
13
3,920.00 kJ/mol  
99+

9th Energy Level
16,963.70 kJ/mol  
15
3,920.00 kJ/mol  
99+

10th Energy Level
48,610.00 kJ/mol  
3
392.00 kJ/mol  
99+

11th Energy Level
54,490.00 kJ/mol  
4
392.00 kJ/mol  
99+

12th Energy Level
60,730.00 kJ/mol  
15
38,000.00 kJ/mol  
23

13th Energy Level
68,950.00 kJ/mol  
4
3,920.00 kJ/mol  
99+

14th Energy Level
75,900.00 kJ/mol  
5
380.00 kJ/mol  
99+

15th Energy Level
83,080.00 kJ/mol  
13
67,700.00 kJ/mol  
32

16th Energy Level
93,400.00 kJ/mol  
7
39,200.00 kJ/mol  
99+

17th Energy Level
99,710.00 kJ/mol  
8
392.00 kJ/mol  
99+

18th Energy Level
4,196.00 kJ/mol  
99+
3,920.00 kJ/mol  
99+

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

20th Energy Level
419.00 kJ/mol  
99+
392.00 kJ/mol  
99+

21st Energy Level
419.20 kJ/mol  
99+
392.00 kJ/mol  
99+

22nd Energy Level
419.00 kJ/mol  
99+
392.00 kJ/mol  
99+

23rd Energy Level
419.20 kJ/mol  
99+
392.80 kJ/mol  
99+

24th Energy Level
419.20 kJ/mol  
99+
392.00 kJ/mol  
99+

25th Energy Level
419.20 kJ/mol  
99+
392.00 kJ/mol  
99+

26th Energy Level
419.20 kJ/mol  
99+
392.80 kJ/mol  
99+

27th Energy Level
419.20 kJ/mol  
99+
392.00 kJ/mol  
99+

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

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

30th Energy Level
419.00 kJ/mol  
99+
677.00 kJ/mol  
31

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

Electron Work Function
2.30 eV  
99+
4.07 eV  
33

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

Atomic

Atomic Number
19  
99+
87  
31

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

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
19  
99+
87  
31

Number of Neutrons
20  
99+
136  
18

Number of Electrons
19  
99+
87  
31

Radius of an Atom
  
  

Atomic Radius
227.00 pm  
4
348.00 pm  
1

Covalent Radius
203.00 pm  
9
260.00 pm  
1

Van der Waals Radius
275.00 pm  
7
348.00 pm  
1

Atomic Weight
39.10 amu  
99+
223.00 amu  
27

Atomic Volume
45.46 cm3/mol  
4
71.00 cm3/mol  
2

Adjacent Atomic Numbers
  
  

Previous Element
Aluminium
  
Polonium
  

Next Element
Calcium
  
Radium
  

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

Lattice Constant
532.80 pm  
13
440.00 pm  
21

Lattice Angles
π/2, π/2, π/2  
-  

Lattice C/A Ratio
1.69  
10
1.56  
99+

Mechanical

Density
  
  

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

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

Tensile Strength
16.00 MPa  
99+
50.00 MPa  
38

Viscosity
0.00  
9
0.00  
25

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)  
16
0.00 (Pa)  
37

Vapor Pressure at 2000 K
0.00 (Pa)  
34
0.00 (Pa)  
24

Elasticity properties
  
  

Shear Modulus
1.30 GPa  
99+
3.60 GPa  
99+

Bulk Modulus
3.10 GPa  
99+
6.00 GPa  
99+

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

Poisson Ratio
0.35  
9
0.44  
3

Other Mechanical Properties
-  
-  

Magnetic

Magnetic Characteristics
  
  

Specific Gravity
0.86  
99+
0.87  
99+

Magnetic Ordering
Paramagnetic  
Paramagnetic  

Permeability
0.00 H/m  
13
0.00 H/m  
13

Susceptibility
0.00  
23
0.00  
24

Electrical Properties
  
  

Electrical Property
Conductor  
Poor Conductor  

Resistivity
72.00 nΩ·m  
37
3.00 nΩ·m  
99+

Electrical Conductivity
0.14 106/cm Ω  
16
0.03 106/cm Ω  
99+

Electron Affinity
48.40 kJ/mol  
27
0.70 kJ/mol  
99+

Thermal

Specific Heat
0.75 J/(kg K)  
6
0.15 J/(kg K)  
37

Molar Heat Capacity
29.60 J/mol·K  
8
27.00 J/mol·K  
29

Thermal Conductivity
102.50 W/m·K  
15
15.00 W/m·K  
99+

Critical Temperature
2,223.00 K  
14
300.00 K  
99+

Thermal Expansion
83.30 µm/(m·K)  
3
18.90 µm/(m·K)  
25

Enthalpy
  
  

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

Enthalpy of Fusion
2.32 kJ/mol  
99+
2.30 kJ/mol  
99+

Enthalpy of Atomization
89.50 kJ/mol  
99+
71.00 kJ/mol  
99+

Standard Molar Entropy
64.70 J/mol.K  
19
42.00 J/mol.K  
99+

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