Symbol
K
  
Co
  
Period Number
4
  
4
  
Block
s block
  
d block
  
Element Family
Alkali
  
Transition Metal
  
Space Group Name
Im_ 3m
  
P63/mmc
  
Interesting Facts
- In the list of most abundant element Potassium is ranked 7th.
- Potassium can easily be sliced (chopped) down using knife.
  
- The main source of Cobalt is as a by-product of copper and nickel metal mining.
- Cobalt metal can be obtained from other elements like Oxygen, Sulfur and Arsenic.
- It s also used in electroplating process as it exhibits anti cession properties.
  
Sources
Found in Minerals, Mining
  
Found in Compounds, Mining, Ores of Minerals
  
History
  
  
Who Discovered
Humphry Davy
  
Georg Brandt
  
Discovery
In 1807
  
In 1732
  
Abundance
  
  
Abundance In Earth's Crust
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.
  
- Its alloys with aluminum and nickel are used to make powerful magnets.
-
Few other alloys exhibit high-temperature strength and hence they are used in Turbines of Jet and Gas engine.
  
Industrial Uses
Ammunition Industry, Chemical Industry
  
Chemical Industry, Electrical Industry, Electronic Industry
  
Medical Uses
Pharmaceutical Industry
  
Pharmaceutical Industry
  
Other Uses
NA
  
Alloys
  
Biological Properties
  
  
Toxicity
Toxic
  
Toxic
  
Present in Human Body
Yes
  
Yes
  
In Blood
1,620.00 Blood/mg dm-3
  
2
0.04 Blood/mg dm-3
  
18
In Bone
2,100.00 p.p.m.
  
3
0.04 p.p.m.
  
27
Melting Point
1,495.00 °C
  
29
Boiling Point
2,870.00 °C
  
34
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery Gray
  
Gray
  
Luster
NA
  
Metallic
  
Hardness
  
  
Vickers Hardness
Not Available
  
1,043.00 MPa
  
11
Speed of Sound
2,000.00 m/s
  
99+
4,720.00 m/s
  
14
Optical Properties
  
  
Reflectivity
Not Available
  
Allotropes
No
  
Yes
  
α Allotropes
Not Available
  
α-Cobalt
  
β Allotropes
Not Available
  
β-Cobalt
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
K
  
Co
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
418.80 kJ/mol
  
99+
760.40 kJ/mol
  
19
2nd Energy Level
3,052.00 kJ/mol
  
5
1,648.00 kJ/mol
  
31
3rd Energy Level
4,420.00 kJ/mol
  
8
3,232.00 kJ/mol
  
22
4th Energy Level
5,877.00 kJ/mol
  
9
4,950.00 kJ/mol
  
19
5th Energy Level
7,975.00 kJ/mol
  
8
7,670.00 kJ/mol
  
12
6th Energy Level
9,590.00 kJ/mol
  
13
9,840.00 kJ/mol
  
12
7th Energy level
11,343.00 kJ/mol
  
17
12,440.00 kJ/mol
  
11
8th Energy Level
14,944.00 kJ/mol
  
13
15,230.00 kJ/mol
  
12
9th Energy Level
16,963.70 kJ/mol
  
15
17,959.00 kJ/mol
  
13
10th Energy Level
48,610.00 kJ/mol
  
3
26,570.00 kJ/mol
  
7
11th Energy Level
54,490.00 kJ/mol
  
4
29,400.00 kJ/mol
  
8
12th Energy Level
60,730.00 kJ/mol
  
4
32,400.00 kJ/mol
  
8
13th Energy Level
68,950.00 kJ/mol
  
4
36,600.00 kJ/mol
  
8
14th Energy Level
75,900.00 kJ/mol
  
5
39,700.00 kJ/mol
  
9
15th Energy Level
83,080.00 kJ/mol
  
6
42,800.00 kJ/mol
  
12
16th Energy Level
93,400.00 kJ/mol
  
7
49,396.00 kJ/mol
  
11
17th Energy Level
99,710.00 kJ/mol
  
8
52,737.00 kJ/mol
  
13
18th Energy Level
Not Available
  
134,810.00 kJ/mol
  
1
19th Energy Level
Not Available
  
145,170.00 kJ/mol
  
2
20th Energy Level
Not Available
  
154,700.00 kJ/mol
  
4
21st Energy Level
Not Available
  
167,400.00 kJ/mol
  
4
22nd Energy Level
Not Available
  
178,100.00 kJ/mol
  
3
23rd Energy Level
Not Available
  
189,300.00 kJ/mol
  
3
Electrochemical Equivalent
1.46 g/amp-hr
  
99+
1.10 g/amp-hr
  
99+
Other Chemical Properties
Chemical Stability, Flammability, Ionization, Solubility
  
Chemical Stability, Ionization
  
Electron Configuration
[Ar] 4s1
  
[Ar] 3d2 4s2
  
Crystal Structure
Body Centered Cubic (BCC)
  
Hexagonal Close Packed (HCP)
  
Crystal Lattice
BCC-Crystal-Structure-.jpg#100
  
HCP-Crystal-Structure-of-Cobalt.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
45.46 cm3/mol
  
3
10.64 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
10.40 (-eV)
  
99+
95.20 (-eV)
  
10
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, 2 π/3
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
0.86 g/cm3
  
99+
4.51 g/cm3
  
99+
Density When Liquid (at m.p.)
0.83 g/cm3
  
99+
4.11 g/cm3
  
99+
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Poisson Ratio
Not Available
  
Other Mechanical Properties
NA
  
Ductile
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Poor Conductor
  
Resistivity
420.00 nΩ·m
  
12
Electrical Conductivity
0.14 106/cm Ω
  
14
0.02 106/cm Ω
  
99+
Electron Affinity
48.40 kJ/mol
  
22
7.60 kJ/mol
  
37
Specific Heat
0.75 J/(kg K)
  
6
0.52 J/(kg K)
  
9
Molar Heat Capacity
29.60 J/mol·K
  
6
25.06 J/mol·K
  
99+
Thermal Conductivity
102.50 W/m·K
  
15
21.90 W/m·K
  
99+
Critical Temperature
Not Available
  
Thermal Expansion
83.30 µm/(m·K)
  
3
8.60 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
77.50 kJ/mol
  
99+
429.00 kJ/mol
  
15
Enthalpy of Fusion
2.32 kJ/mol
  
99+
15.48 kJ/mol
  
19
Enthalpy of Atomization
89.50 kJ/mol
  
99+
468.60 kJ/mol
  
15
Standard Molar Entropy
64.70 J/mol.K
  
18
27.30 J/mol.K
  
99+