Symbol
Rh
  
Ni
  
Period Number
5
  
4
  
Block
d block
  
d block
  
Element Family
Transition Metal
  
Transition Metal
  
Space Group Name
Fm_ 3m
  
Fm_ 3m
  
Interesting Facts
- 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.
  
- Zinc metal found (obtain) in many forms like granules, foil, dust and in a powder form.
- After iron, Zinc metal the second most abundant element in the earth crust.
  
Sources
Earth's crust, Found As a By-product, Found in Minerals, Mining
  
Found in Minerals, Mining, Ores of Minerals
  
History
  
  
Who Discovered
William Hyde Wollaston
  
Axel Fredrik Cronstedt
  
Discovery
In 1804
  
In 1751
  
Abundance
  
  
Abundance In Sun
~0.0000002 %
  
25
Abundance In Earth's Crust
Abundance In Oceans
Not Available
  
Abundance In Humans
Not Available
  
Uses & Benefits
- 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.
  
- It has corrosion resistance and hence it is used to plate other metals.
- Its alloys are very useful; Nichrome alloy is used in the hot coil of toasters and electric oven.
  
Industrial Uses
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
  
Automobile Industry, Electrical Industry, Electronic Industry
  
Medical Uses
NA
  
NA
  
Other Uses
Alloys
  
Alloys
  
Biological Properties
  
  
Toxicity
NA
  
Toxic
  
Present in Human Body
No
  
Yes
  
In Blood
Not Available
  
0.05 Blood/mg dm-3
  
17
In Bone
Not Available
  
0.70 p.p.m.
  
18
Melting Point
1,966.00 °C
  
12
1,453.00 °C
  
31
Boiling Point
3,727.00 °C
  
17
2,732.00 °C
  
38
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery White
  
Silver
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Vickers Hardness
1,100.00 MPa
  
9
Speed of Sound
4,700.00 m/s
  
15
4,900.00 m/s
  
12
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
Rh
  
Ni
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Not Available
  
Allred Rochow Electronegativity
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
719.70 kJ/mol
  
29
737.10 kJ/mol
  
25
2nd Energy Level
1,740.00 kJ/mol
  
26
1,753.00 kJ/mol
  
25
3rd Energy Level
2,997.00 kJ/mol
  
27
3,395.00 kJ/mol
  
17
4th Energy Level
Not Available
  
5,300.00 kJ/mol
  
15
5th Energy Level
Not Available
  
7,339.00 kJ/mol
  
15
6th Energy Level
Not Available
  
10,400.00 kJ/mol
  
9
7th Energy level
Not Available
  
12,800.00 kJ/mol
  
10
8th Energy Level
Not Available
  
15,600.00 kJ/mol
  
10
9th Energy Level
Not Available
  
18,600.00 kJ/mol
  
10
10th Energy Level
Not Available
  
21,670.00 kJ/mol
  
14
11th Energy Level
Not Available
  
30,970.00 kJ/mol
  
7
12th Energy Level
Not Available
  
34,000.00 kJ/mol
  
7
13th Energy Level
Not Available
  
37,100.00 kJ/mol
  
7
14th Energy Level
Not Available
  
41,500.00 kJ/mol
  
8
15th Energy Level
Not Available
  
44,800.00 kJ/mol
  
10
16th Energy Level
Not Available
  
48,100.00 kJ/mol
  
12
17th Energy Level
Not Available
  
55,101.00 kJ/mol
  
11
18th Energy Level
Not Available
  
58,570.00 kJ/mol
  
12
19th Energy Level
Not Available
  
148,700.00 kJ/mol
  
1
20th Energy Level
Not Available
  
159,000.00 kJ/mol
  
3
21st Energy Level
Not Available
  
169,400.00 kJ/mol
  
3
22nd Energy Level
Not Available
  
182,700.00 kJ/mol
  
2
23rd Energy Level
Not Available
  
194,000.00 kJ/mol
  
2
Electrochemical Equivalent
1.28 g/amp-hr
  
99+
1.10 g/amp-hr
  
99+
Other Chemical Properties
Anti Corrosion, Ionization, Radioactive Isotopes
  
Anti Corrosion, Ionization, Radioactive Isotopes
  
Electron Configuration
[Kr] 4d8 5s1
  
[Ar] 3d8 4s2 Or [Ar] 3d9 4s1
  
Crystal Structure
Face Centered Cubic (FCC)
  
Face Centered Cubic (FCC)
  
Crystal Lattice
FCC-Crystal-Structure-of-Rhodium.jpg#100
  
FCC-Crystal-Structure-of-Nickel.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Weight
102.91 amu
  
99+
Atomic Volume
8.30 cm3/mol
  
99+
6.59 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
64.00 (-eV)
  
22
42.00 (-eV)
  
99+
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
12.41 g/cm3
  
28
8.91 g/cm3
  
99+
Density When Liquid (at m.p.)
10.70 g/cm3
  
14
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 1000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
Malleable
  
Ductile
  
Magnetic Characteristics
  
  
Magnetic Ordering
Paramagnetic
  
Ferromagnetic
  
Permeability
Not Available
  
Susceptibility
Not Available
  
Electrical Properties
  
  
Electrical Property
Conductor
  
Conductor
  
Resistivity
43.30 nΩ·m
  
99+
Electrical Conductivity
0.21 106/cm Ω
  
8
0.14 106/cm Ω
  
13
Electron Affinity
109.70 kJ/mol
  
7
112.00 kJ/mol
  
6
Specific Heat
0.24 J/(kg K)
  
22
0.44 J/(kg K)
  
13
Molar Heat Capacity
24.98 J/mol·K
  
99+
26.07 J/mol·K
  
31
Thermal Conductivity
150.00 W/m·K
  
9
90.90 W/m·K
  
18
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
8.20 µm/(m·K)
  
99+
13.40 µm/(m·K)
  
28
Enthalpy
  
  
Enthalpy of Vaporization
495.40 kJ/mol
  
12
371.80 kJ/mol
  
20
Enthalpy of Fusion
21.76 kJ/mol
  
10
17.57 kJ/mol
  
14
Enthalpy of Atomization
556.50 kJ/mol
  
12
422.60 kJ/mol
  
17
Standard Molar Entropy
31.50 J/mol.K
  
99+
29.90 J/mol.K
  
99+