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Lanthanum vs Potassium


Potassium vs Lanthanum


Periodic Table

Symbol
La   
K   

Group Number
Not Available   
1   
17

Period Number
6   
4   

Block
f block   
s block   

Element Family
Lanthanide   
Alkali   

CAS Number
7439910   
99+
7440097   
99+

Space Group Name
P63/mmc   
Im_ 3m   

Space Group Number
194.00   
5
229.00   
1

Facts

Interesting Facts
  • Lanthanum metal is highly malleable, ductile and sectile.
  • If exposed to air Lanthanum metal oxidizes rapidly.
  
  • In the list of most abundant element Potassium is ranked 7th.
  • Potassium can easily be sliced (chopped) down using knife.
  

Sources
Found in Minerals, Mining, Ores of Minerals   
Found in Minerals, Mining   

History
  
  

Who Discovered
Carl Gustaf Mosander   
Humphry Davy   

Discovery
In 1838   
In 1807   

Abundance
  
  

Abundance In Universe
2 * 10-7 %   
22
3 * 10-4 %   
9

Abundance In Sun
~0.0000002 %   
25
~0.0004 %   
9

Abundance In Meteorites
0.00 %   
32
0.07 %   
9

Abundance In Earth's Crust
0.00 %   
19
1.50 %   
6

Abundance In Oceans
0.00 %   
29
0.04 %   
3

Abundance In Humans
Not Available   
0.20 %   
2

Uses

Uses & Benefits
  • It has no commercial uses, but its alloys are in high demand. Lanthanum and Nickel alloy is used for the hydrogen gas storage.
  • The best-known use for mischmetal alloy of Lanthanum is; as a ‘flints’ for cigarette lighters.
  
  • 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.
  

Industrial Uses
Electrical Industry, Electronic Industry   
Ammunition Industry, Chemical Industry   

Medical Uses
NA   
Pharmaceutical Industry   

Other Uses
Alloys, Mirror Manufacturing   
NA   

Biological Properties
  
  

Toxicity
Low Toxic   
Toxic   

Present in Human Body
Yes   
Yes   

In Blood
Not Available   
1,620.00 Blood/mg dm-3   
2

In Bone
0.08 p.p.m.   
24
2,100.00 p.p.m.   
3

Physical Properties

Melting Point
920.00 °C   
99+
63.65 °C   
99+

Boiling Point
3,469.00 °C   
18
774.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silvery White   
Silvery Gray   

Luster
NA   
NA   

Hardness
  
  

Mohs Hardness
2.50   
14
0.40   
23

Brinell Hardness
350.00 MPa   
30
0.36 MPa   
99+

Vickers Hardness
360.00 MPa   
26
Not Available   

Speed of Sound
2,475.00 m/s   
37
2,000.00 m/s   
99+

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
La   
K   

Isotopes
  
  

Known Isotopes
31   
8
20   
19

Electronegativity
  
  

Pauling Electronegativity
1.10   
99+
0.82   
99+

Sanderson Electronegativity
Not Available   
0.45   
31

Allred Rochow Electronegativity
1.08   
31
0.91   
39

Mulliken-Jaffe Electronegativity
Not Available   
0.73   
23

Allen Electronegativity
Not Available   
0.73   
99+

Electropositivity
  
  

Pauling Electropositivity
2.90   
10
3.18   
3

Ionization Energies
  
  

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

2nd Energy Level
1,067.00 kJ/mol   
99+
3,052.00 kJ/mol   
5

3rd Energy Level
1,850.30 kJ/mol   
99+
4,420.00 kJ/mol   
8

4th Energy Level
4,819.00 kJ/mol   
22
5,877.00 kJ/mol   
9

5th Energy Level
5,940.00 kJ/mol   
25
7,975.00 kJ/mol   
8

6th Energy Level
Not Available   
9,590.00 kJ/mol   
13

7th Energy level
Not Available   
11,343.00 kJ/mol   
17

8th Energy Level
Not Available   
14,944.00 kJ/mol   
13

9th Energy Level
Not Available   
16,963.70 kJ/mol   
15

10th Energy Level
Not Available   
48,610.00 kJ/mol   
3

11th Energy Level
Not Available   
54,490.00 kJ/mol   
4

12th Energy Level
Not Available   
60,730.00 kJ/mol   
4

13th Energy Level
Not Available   
68,950.00 kJ/mol   
4

14th Energy Level
Not Available   
75,900.00 kJ/mol   
5

15th Energy Level
Not Available   
83,080.00 kJ/mol   
6

16th Energy Level
Not Available   
93,400.00 kJ/mol   
7

17th Energy Level
Not Available   
99,710.00 kJ/mol   
8

Electrochemical Equivalent
1.73 g/amp-hr   
99+
1.46 g/amp-hr   
99+

Electron Work Function
3.50 eV   
31
2.30 eV   
99+

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

Atomic Properties

Atomic Number
57   
99+
19   
99+

Electron Configuration
[Xe] 5d2 6s2   
[Ar] 4s1   

Crystal Structure
Double Hexagonal Close Packed (DHCP)   
Body Centered Cubic (BCC)   

Crystal Lattice
DHCP-Crystal-Structure-of-Lanthanum.jpg#100   
BCC-Crystal-Structure-.jpg#100   

Atom
  
  

Number of Protons
57   
99+
19   
99+

Number of Neutrons
82   
99+
20   
99+

Number of Electrons
57   
99+
19   
99+

Radius of an Atom
  
  

Atomic Radius
187.00 pm   
8
227.00 pm   
3

Covalent Radius
207.00 pm   
6
203.00 pm   
9

Van der Waals Radius
240.00 pm   
13
275.00 pm   
5

Atomic Weight
138.91 amu   
99+
39.10 amu   
99+

Atomic Volume
20.73 cm3/mol   
16
45.46 cm3/mol   
3

Adjacent Atomic Numbers
  
  

Previous Element
Barium
  
Aluminium
  

Next Element
Cerium
  
Calcium
  

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

Lattice Constant
377.20 pm   
28
532.80 pm   
12

Lattice Angles
π/2, π/2, 2 π/3   
π/2, π/2, π/2   

Lattice C/A Ratio
1.62   
2
Not Available   

Mechanical Properties

Density
  
  

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

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

Tensile Strength
Not Available   
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 2000 K
0.98 (Pa)   
15
Not Available   

Elasticity properties
  
  

Shear Modulus
14.30 GPa   
40
1.30 GPa   
99+

Bulk Modulus
27.90 GPa   
99+
3.10 GPa   
99+

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

Poisson Ratio
0.28   
17
Not Available   

Other Mechanical Properties
Ductile   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
6.17   
99+
0.86   
99+

Magnetic Ordering
Paramagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
Conductor   
Conductor   

Resistivity
615.00 nΩ·m   
7
72.00 nΩ·m   
37

Electrical Conductivity
0.01 106/cm Ω   
99+
0.14 106/cm Ω   
14

Electron Affinity
48.00 kJ/mol   
23
48.40 kJ/mol   
22

Thermal Properties

Specific Heat
0.19 J/(kg K)   
32
0.75 J/(kg K)   
6

Molar Heat Capacity
27.11 J/mol·K   
21
29.60 J/mol·K   
6

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

Critical Temperature
Not Available   
2,223.00 K   
3

Thermal Expansion
12.10 µm/(m·K)   
32
83.30 µm/(m·K)   
3

Enthalpy
  
  

Enthalpy of Vaporization
399.60 kJ/mol   
17
77.50 kJ/mol   
99+

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

Enthalpy of Atomization
431.00 kJ/mol   
16
89.50 kJ/mol   
99+

Standard Molar Entropy
56.90 J/mol.K   
23
64.70 J/mol.K   
18

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