Symbol
Mg
  
Rh
  
Period Number
3
  
5
  
Block
s block
  
d block
  
Element Family
Alkaline Earth
  
Transition Metal
  
Space Group Name
P63/mmc
  
Fm_ 3m
  
Interesting Facts
- Magnesium ions are present in every chlorophyll of every green plant .
- Controlling Magnesium fire by pouring water on it will result in explosions.
  
- Rhodium is the rarest element out of all non-radioactive metals on the earth .
- Rhodium is one of the most durable and hard metal, which also have high reflectance.
  
Sources
By Electrolysis Process, In Ocean, Mining
  
Earth's crust, Found As a By-product, Found in Minerals, Mining
  
History
  
  
Who Discovered
Joseph Black
  
William Hyde Wollaston
  
Discovery
In 1755
  
In 1804
  
Abundance
  
  
Abundance In Sun
~0.0000002 %
  
25
Abundance In Earth's Crust
Abundance In Oceans
Not Available
  
Abundance In Humans
Not Available
  
Uses & Benefits
- Magnesium aluminum alloy improves the mechanical strength and welding characteristics and hence it is used in aeroplane and car manufacturing.
-
It is also used to remove sulfur from the molten iron and steel.
  
- Rhodium metal is mainly used in catalytic converters for cars as it reduces nitrogen oxides in exhaust gases.
- It is used as an industrial catalyst for nitric acid, acetic acid, hydrogenation reaction, etc.
  
Industrial Uses
Aerospace Industry, Ammunition Industry, Automobile Industry, Chemical Industry, Pharmaceutical Industry
  
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Surgical Instruments Manufacturing
  
Alloys
  
Biological Properties
  
  
Toxicity
Non Toxic
  
NA
  
Present in Human Body
Yes
  
No
  
In Blood
37.80 Blood/mg dm-3
  
5
Not Available
  
In Bone
1,800.00 p.p.m.
  
4
Not Available
  
Melting Point
1,966.00 °C
  
12
Boiling Point
1,107.00 °C
  
99+
3,727.00 °C
  
17
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Silvery White
  
Luster
NA
  
Metallic
  
Hardness
  
  
Vickers Hardness
Not Available
  
1,100.00 MPa
  
9
Speed of Sound
4,940.00 m/s
  
11
4,700.00 m/s
  
15
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
Mg
  
Rh
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
737.70 kJ/mol
  
24
719.70 kJ/mol
  
29
2nd Energy Level
1,450.70 kJ/mol
  
99+
1,740.00 kJ/mol
  
26
3rd Energy Level
7,732.70 kJ/mol
  
5
2,997.00 kJ/mol
  
27
4th Energy Level
10,542.50 kJ/mol
  
4
Not Available
  
5th Energy Level
13,630.00 kJ/mol
  
3
Not Available
  
6th Energy Level
18,020.00 kJ/mol
  
3
Not Available
  
7th Energy level
21,711.00 kJ/mol
  
3
Not Available
  
8th Energy Level
25,661.00 kJ/mol
  
3
Not Available
  
9th Energy Level
31,653.00 kJ/mol
  
3
Not Available
  
10th Energy Level
35,458.00 kJ/mol
  
5
Not Available
  
11th Energy Level
169,988.00 kJ/mol
  
1
Not Available
  
12th Energy Level
189,368.00 kJ/mol
  
1
Not Available
  
Electrochemical Equivalent
0.45 g/amp-hr
  
99+
1.28 g/amp-hr
  
99+
Other Chemical Properties
Corrosion, Highly Inflammable, Ionization, Solubility
  
Anti Corrosion, Ionization, Radioactive Isotopes
  
Electron Configuration
[Ne] 3s2
  
[Kr] 4d8 5s1
  
Crystal Structure
Hexagonal Close Packed (HCP)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
HCP-Crystal-Structure-of-Magnesium.jpg#100
  
FCC-Crystal-Structure-of-Rhodium.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
102.91 amu
  
99+
Atomic Volume
13.97 cm3/mol
  
37
8.30 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
40.00 (-eV)
  
99+
64.00 (-eV)
  
22
Lattice Angles
π/2, π/2, 2 π/3
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
1.74 g/cm3
  
99+
12.41 g/cm3
  
28
Density When Liquid (at m.p.)
1.58 g/cm3
  
99+
10.70 g/cm3
  
14
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
NA
  
Malleable
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Paramagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
43.90 nΩ·m
  
99+
43.30 nΩ·m
  
99+
Electrical Conductivity
0.23 106/cm Ω
  
7
0.21 106/cm Ω
  
8
Electron Affinity
0.00 kJ/mol
  
40
109.70 kJ/mol
  
7
Specific Heat
1.02 J/(kg K)
  
4
0.24 J/(kg K)
  
22
Molar Heat Capacity
24.87 J/mol·K
  
99+
24.98 J/mol·K
  
99+
Thermal Conductivity
156.00 W/m·K
  
8
150.00 W/m·K
  
9
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
24.80 µm/(m·K)
  
15
8.20 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
128.70 kJ/mol
  
99+
495.40 kJ/mol
  
12
Enthalpy of Fusion
8.95 kJ/mol
  
39
21.76 kJ/mol
  
10
Enthalpy of Atomization
148.50 kJ/mol
  
99+
556.50 kJ/mol
  
12
Standard Molar Entropy
32.70 J/mol.K
  
99+
31.50 J/mol.K
  
99+