Symbol
Ga
  
Hf
  
Period Number
4
  
6
  
Block
p block
  
d block
  
Element Family
Post-Transition
  
Transition Metal
  
Space Group Name
Cmca
  
P63/mmc
  
Interesting Facts
- A gram of Gallium metal can be bought for only three dollars.
- Gallium metal found in ores of following things Coal, Bauxite, Diaspore, Sphalerite, Germanite and Zinc.
  
- Hafnium metal is highly reactive, hence not found free in nature.
- Hafnium metal as predicated after Mendeleev finished his periodic table.
  
Sources
Earth's crust, Found in Minerals, Mining, Ores of Minerals
  
By-product Zirconium Refining
  
History
  
  
Who Discovered
Lecoq de Boisbaudran
  
Dirk Coster and George de Hevesy
  
Discovery
In 1875
  
In 1922
  
Abundance
  
  
Abundance In Sun
~0.000004 %
  
16
~0.0000001 %
  
26
Abundance In Earth's Crust
Uses & Benefits
- Gallium arsenide is a very important component of many semiconductors and led manufacturing.
- Gallium nitride is also know as a semiconductor and it is used in Blu-ray technology, mobile smartphones and LED.
  
- It has an ability to absorb neutrons and hence it is used to make control rods in nuclear submarines. And this metal is also used in Plasma welding torches.
-
It alloys with iron, titanium and niobium are very useful.
  
Industrial Uses
Electrical Industry, Electronic Industry
  
Ammunition Industry
  
Medical Uses
Surgical Instruments Manufacturing
  
NA
  
Other Uses
Alloys
  
Alloys, In Nuclear Reactors, Nuclear Research, Research Purposes
  
Biological Properties
  
  
Toxicity
Non Toxic
  
Toxic
  
Present in Human Body
Yes
  
No
  
In Blood
0.08 Blood/mg dm-3
  
13
Not Available
  
Melting Point
2,150.00 °C
  
10
Boiling Point
2,403.00 °C
  
99+
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery White
  
Gray
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Brinell Hardness
1,450.00 MPa
  
6
Vickers Hardness
Not Available
  
1,520.00 MPa
  
5
Speed of Sound
2,740.00 m/s
  
31
3,010.00 m/s
  
27
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Ga
  
Hf
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
578.80 kJ/mol
  
99+
658.50 kJ/mol
  
40
2nd Energy Level
1,979.30 kJ/mol
  
13
1,440.00 kJ/mol
  
99+
3rd Energy Level
2,963.00 kJ/mol
  
28
2,250.00 kJ/mol
  
99+
4th Energy Level
6,180.00 kJ/mol
  
8
3,216.00 kJ/mol
  
99+
Electrochemical Equivalent
0.87 g/amp-hr
  
99+
1.66 g/amp-hr
  
99+
Other Chemical Properties
Ionization, Radioactive Isotopes
  
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Ar] 3d10 4s2 4p1
  
[Xe] 4f14 5d2 6s2
  
Crystal Structure
Orthorhombic (ORTH)
  
Hexagonal Close Packed (HCP)
  
Crystal Lattice
ORTH-Crystal-Structure-of-Gallium.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
11.80 cm3/mol
  
99+
13.60 cm3/mol
  
38
Adjacent Atomic Numbers
  
  
Valence Electron Potential
69.70 (-eV)
  
19
81.00 (-eV)
  
16
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, 2 π/3
  
Lattice C/A Ratio
Not Available
  
Density
  
  
Density At Room Temperature
5.91 g/cm3
  
99+
13.31 g/cm3
  
26
Density When Liquid (at m.p.)
6.10 g/cm3
  
99+
12.00 g/cm3
  
12
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Shear Modulus
Not Available
  
Bulk Modulus
Not Available
  
Other Mechanical Properties
NA
  
Ductile, Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Diamagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Semiconductor
  
Conductor
  
Resistivity
270.00 nΩ·m
  
15
331.00 nΩ·m
  
14
Electrical Conductivity
0.07 106/cm Ω
  
29
0.03 106/cm Ω
  
39
Electron Affinity
28.90 kJ/mol
  
31
0.00 kJ/mol
  
40
Specific Heat
0.37 J/(kg K)
  
16
0.14 J/(kg K)
  
37
Molar Heat Capacity
25.86 J/mol·K
  
35
25.73 J/mol·K
  
36
Thermal Conductivity
40.60 W/m·K
  
34
23.00 W/m·K
  
99+
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
18.00 µm/(m·K)
  
24
5.90 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
256.10 kJ/mol
  
36
661.10 kJ/mol
  
5
Enthalpy of Fusion
5.59 kJ/mol
  
99+
25.10 kJ/mol
  
8
Enthalpy of Atomization
276.10 kJ/mol
  
39
703.00 kJ/mol
  
5
Standard Molar Entropy
40.80 J/mol.K
  
38
43.60 J/mol.K
  
34