Symbol
Ce
Rh
Group Number
39
0
17
👆🏻
Period Number
65
2
7
👆🏻
Block
f block
d block
Element Family
Lanthanide
Transition Metal
CAS Number
74404517440166
7429905
54386242
👆🏻
Space Group Name
P63/mmc
Fm_ 3m
Space Group Number
194.00225.00
11
276
👆🏻
Interesting Facts
- Cerium is a rare earth metal but still it is not rare at all.
- It’s non-toxic compound Cerium sulfide has a rich red color and it is used as a pigment.
- Cerium metal is also used in Flat screen TVs, light bulb, floodlights, etc.
- 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
Found in Minerals, Mining, Ores of Minerals
Earth's crust, Found As a By-product, Found in Minerals, Mining
History
Who Discovered
Martin Heinrich Klaproth, Jöns Jakob Berzelius, Wilhelm Hisinger
William Hyde Wollaston
Discovery
In 1803
In 1804
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
0.00 %0.00 %
0
0.1
👆🏻
Abundance In Meteorites
0.00 %0.00 %
0
22
👆🏻
Abundance In Earth's Crust
0.01 %0.00 %
1E-37
8.1
👆🏻
Abundance In Oceans
0.00 %-
0
1.1
👆🏻
Abundance In Humans
0.00 %0.00 %
0
1.4
👆🏻
Uses & Benefits
- It is used to include flints for cigarette lighters.
- Its compound Cerium (Ill) Oxide is used as a catalyst; it is put inside the walls of the oven as it prevents from the buildup of cooking residues.
- 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
Chemical Industry
Aerospace Industry, Automobile Industry, Electrical Industry, Electronic Industry
Medical Uses
Medical Research
-
Other Uses
Alloys
Alloys
Biological Properties
Toxicity
Moderately Toxic
-
Present in Human Body
✔
✘
✔
✘
In Blood
0.00 Blood/mg dm-30.00 Blood/mg dm-3
0
1970
👆🏻
In Bone
2.70 p.p.m.0.00 p.p.m.
0
170000
👆🏻
Melting Point
795.00 °C1,966.00 °C
-38.83
3410
👆🏻
Boiling Point
3,257.00 °C3,727.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery White
Silvery White
Luster
Lustrous
Metallic
Hardness
Mohs Hardness
2.506.00
0.2
8.5
👆🏻
Brinell Hardness
186.00 MPa980.00 MPa
0.14
3490
👆🏻
Vickers Hardness
210.00 MPa1,100.00 MPa
0
3920
👆🏻
Speed of Sound
2,100.00 m/s4,700.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
2.202.40
0.155
3.41
👆🏻
Reflectivity
68.00 %84.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Ce
Rh
Isotopes
Known Isotopes
3016
0
38
👆🏻
Electronegativity
Pauling Electronegativity
1.122.28
0
2.6
👆🏻
Sanderson Electronegativity
1.122.28
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.081.45
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.122.28
0.62
2.48
👆🏻
Allen Electronegativity
1.121.56
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.881.72
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
534.40 kJ/mol719.70 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
1,050.00 kJ/mol1,740.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
1,949.00 kJ/mol2,997.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
3,547.00 kJ/mol7,197.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
6,325.00 kJ/mol7,197.00 kJ/mol
392
97510
👆🏻
6th Energy Level
7,490.00 kJ/mol7,197.00 kJ/mol
1007
105800
👆🏻
7th Energy level
5,340.00 kJ/mol7,197.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
5,340.00 kJ/mol3,480.00 kJ/mol
730
125300
👆🏻
9th Energy Level
5,340.00 kJ/mol5,090.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
5,340.00 kJ/mol7,197.00 kJ/mol
392
144300
👆🏻
11th Energy Level
5,340.00 kJ/mol7,197.00 kJ/mol
392
169988
👆🏻
12th Energy Level
5,340.00 kJ/mol7,190.00 kJ/mol
0
189368
👆🏻
13th Energy Level
5,650.00 kJ/mol7,190.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
5,340.00 kJ/mol7,197.00 kJ/mol
380
86450
👆🏻
15th Energy Level
53,400.00 kJ/mol71,900.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
53,400.00 kJ/mol71,900.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
534.40 kJ/mol719.70 kJ/mol
375.7
122200
👆🏻
18th Energy Level
5,340.00 kJ/mol7,197.00 kJ/mol
0
134810
👆🏻
19th Energy Level
534.40 kJ/mol719.70 kJ/mol
375.7
148700
👆🏻
20th Energy Level
534.00 kJ/mol719.00 kJ/mol
0
171200
👆🏻
21st Energy Level
5,346.00 kJ/mol719.70 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
594.00 kJ/mol719.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
5,346.00 kJ/mol719.70 kJ/mol
357.6
198800
👆🏻
24th Energy Level
565.50 kJ/mol719.70 kJ/mol
297.3
195200
👆🏻
25th Energy Level
534.40 kJ/mol719.00 kJ/mol
0
121900
👆🏻
26th Energy Level
565.50 kJ/mol719.70 kJ/mol
357.6
127700
👆🏻
27th Energy Level
565.50 kJ/mol719.70 kJ/mol
0
133800
👆🏻
28th Energy Level
565.50 kJ/mol719.70 kJ/mol
297.3
139800
👆🏻
29th Energy Level
565.50 kJ/mol719.70 kJ/mol
0
148100
👆🏻
30th Energy Level
594.00 kJ/mol719.00 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
1.74 g/amp-hr1.28 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
2.84 eV4.98 eV
2.14
6
👆🏻
Other Chemical Properties
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
Anti Corrosion, Ionization, Radioactive Isotopes
Atomic Number
5845
3
117
👆🏻
Electron Configuration
[Xe] 4f1 5d1 6s2
[Kr] 4d8 5s1
Crystal Structure
Double Hexagonal Close Packed (DHCP)
Face Centered Cubic (FCC)
Crystal Lattice
Atom
Number of Protons
5845
3
117
👆🏻
Number of Neutrons
8258
4
285
👆🏻
Number of Electrons
5845
3
117
👆🏻
Radius of an Atom
Atomic Radius
181.80 pm134.00 pm
0
348
👆🏻
Covalent Radius
204.00 pm142.00 pm
0
260
👆🏻
Van der Waals Radius
235.00 pm200.00 pm
0
348
👆🏻
Atomic Weight
140.12 amu102.91 amu
6.94
294
👆🏻
Atomic Volume
20.67 cm3/mol8.30 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
41.78 (-eV)64.00 (-eV)
0
392.42
👆🏻
Lattice Constant
362.00 pm380.34 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, 2 π/3
π/2, π/2, π/2
Lattice C/A Ratio
1.591.73
0.423
1.9
👆🏻
Density
Density At Room Temperature
6.77 g/cm312.41 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
6.55 g/cm310.70 g/cm3
0.512
41
👆🏻
Tensile Strength
270.00 MPa951.00 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)0.00 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
1.04 (Pa)0.02 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
13.50 GPa150.00 GPa
1.3
222
👆🏻
Bulk Modulus
21.50 GPa275.00 GPa
0
462
👆🏻
Young's Modulus
33.60 GPa380.00 GPa
0
528
👆🏻
Poisson Ratio
0.240.26
0.032
0.47
👆🏻
Other Mechanical Properties
Ductile, Malleable
Malleable
Magnetic Characteristics
Specific Gravity
6.7712.41
0.53
4500
👆🏻
Magnetic Ordering
Paramagnetic
Paramagnetic
Permeability
0.00 H/m0.00 H/m
1.25643E-06
0.0063
👆🏻
Susceptibility
0.000.00
-0.000166
200000
👆🏻
Electrical Properties
Electrical Property
Conductor
Conductor
Resistivity
828.00 nΩ·m43.30 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.01 106/cm Ω0.21 106/cm Ω
0
0.63
👆🏻
Electron Affinity
50.00 kJ/mol109.70 kJ/mol
0
222.8
👆🏻
Specific Heat
0.19 J/(kg K)0.24 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
26.94 J/mol·K24.98 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
11.30 W/m·K150.00 W/m·K
0
429
👆🏻
Critical Temperature
1,071.00 K2,237.00 K
26.3
3695
👆🏻
Thermal Expansion
6.30 µm/(m·K)8.20 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
414.00 kJ/mol495.40 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
5.46 kJ/mol21.76 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
381.00 kJ/mol556.50 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
72.00 J/mol.K31.50 J/mol.K
9.5
198.1
👆🏻