Symbol
Rb
Cr
Group Number
16
0
17
👆🏻
Period Number
54
2
7
👆🏻
Block
s block
d block
Element Family
Alkali
Transition Metal
CAS Number
74401777440473
7429905
54386242
👆🏻
Space Group Name
Im_ 3m
Im_ 3m
Space Group Number
229.00229.00
11
276
👆🏻
Interesting Facts
- Rubidium metal is 16th most common element found in the earth crust.
- Rubidium metal also found in minerals as well as seawater.
- Chromium is highly reactive, hence it is not found free in nature.
- Ores of Chromites mineral are the major source of Chromium metal.
- Almost 90% leather tanning is done with the help of chromium.
Sources
Obtained from Lithium Production.
Found in Minerals, Mining, Ores of metals, Ores of Minerals
History
Who Discovered
Robert Bunsen and Gustav Kirchhoff
Louis Nicolas Vauquelin
Discovery
In 1861
In Between 1797 - 1798
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 %0.30 %
0
22
👆🏻
Abundance In Earth's Crust
0.01 %0.01 %
1E-37
8.1
👆🏻
Abundance In Oceans
0.00 %0.00 %
0
1.1
👆🏻
Abundance In Humans
0.00 %0.00 %
0
1.4
👆🏻
Uses & Benefits
- Rubidium's main application is in the glass manufacturing.
- Rubidium can very easily get ionized and hence it is used for ion engines, but it is still less efficient than that of Caesium.
- It is used to harden the steel and produces a stainless steel and other various alloys.
- It is also used to give proper finish to polished mirrors. Its chromium plates are used in bathroom fittings.
Industrial Uses
-
Automobile Industry, Chemical Industry
Medical Uses
-
-
Other Uses
Alloys, Research Purposes
Alloys
Biological Properties
Toxicity
Non Toxic
Highly Toxic
Present in Human Body
✔
✘
✔
✘
In Blood
2.49 Blood/mg dm-30.11 Blood/mg dm-3
0
1970
👆🏻
In Bone
5.00 p.p.m.0.33 p.p.m.
0
170000
👆🏻
Melting Point
38.89 °C1,857.00 °C
-38.83
3410
👆🏻
Boiling Point
688.00 °C2,672.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Grayish White
Silver
Luster
-
Metallic
Hardness
Mohs Hardness
0.308.50
0.2
8.5
👆🏻
Brinell Hardness
0.22 MPa687.00 MPa
0.14
3490
👆🏻
Vickers Hardness
0.22 MPa1,060.00 MPa
0
3920
👆🏻
Speed of Sound
1,300.00 m/s5,940.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.542.97
0.155
3.41
👆🏻
Reflectivity
52.00 %70.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Rb
Cr
Isotopes
Known Isotopes
2921
0
38
👆🏻
Electronegativity
Pauling Electronegativity
0.821.66
0
2.6
👆🏻
Sanderson Electronegativity
0.311.66
0.22
2.56
👆🏻
Allred Rochow Electronegativity
0.891.56
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
0.691.66
0.62
2.48
👆🏻
Allen Electronegativity
0.711.65
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
3.182.34
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
403.00 kJ/mol26,130.00 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
2,633.00 kJ/mol28,750.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
3,860.00 kJ/mol34,230.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
5,080.00 kJ/mol37,066.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
6,850.00 kJ/mol97,510.00 kJ/mol
392
97510
👆🏻
6th Energy Level
8,140.00 kJ/mol105,800.00 kJ/mol
1007
105800
👆🏻
7th Energy level
9,570.00 kJ/mol114,300.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
13,120.00 kJ/mol125,300.00 kJ/mol
730
125300
👆🏻
9th Energy Level
14,500.00 kJ/mol134,700.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
26,740.00 kJ/mol144,300.00 kJ/mol
392
144300
👆🏻
11th Energy Level
4,030.00 kJ/mol26,130.00 kJ/mol
392
169988
👆🏻
12th Energy Level
4,030.00 kJ/mol28,750.00 kJ/mol
0
189368
👆🏻
13th Energy Level
4,030.00 kJ/mol34,230.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
4,030.00 kJ/mol37,066.00 kJ/mol
380
86450
👆🏻
15th Energy Level
40,300.00 kJ/mol97,510.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
40,300.00 kJ/mol105,800.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
403.00 kJ/mol114,300.00 kJ/mol
375.7
122200
👆🏻
18th Energy Level
4,030.00 kJ/mol125,300.00 kJ/mol
0
134810
👆🏻
19th Energy Level
403.00 kJ/mol134,700.00 kJ/mol
375.7
148700
👆🏻
20th Energy Level
403.00 kJ/mol144,300.00 kJ/mol
0
171200
👆🏻
21st Energy Level
403.00 kJ/mol157,700.00 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
403.00 kJ/mol166,090.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
403.00 kJ/mol653.80 kJ/mol
357.6
198800
👆🏻
24th Energy Level
403.00 kJ/mol653.80 kJ/mol
297.3
195200
👆🏻
25th Energy Level
403.00 kJ/mol653.80 kJ/mol
0
121900
👆🏻
26th Energy Level
403.00 kJ/mol653.80 kJ/mol
357.6
127700
👆🏻
27th Energy Level
403.00 kJ/mol652.90 kJ/mol
0
133800
👆🏻
28th Energy Level
403.00 kJ/mol653.80 kJ/mol
297.3
139800
👆🏻
29th Energy Level
403.00 kJ/mol653.80 kJ/mol
0
148100
👆🏻
30th Energy Level
403.00 kJ/mol653.80 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
3.19 g/amp-hr0.32 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
2.16 eV4.50 eV
2.14
6
👆🏻
Other Chemical Properties
Corrosion, Ionization, Radioactive Isotopes, Radioactivity
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility
Atomic Number
3724
3
117
👆🏻
Electron Configuration
[Kr] 5s1
[Ar] 3d5 4s1
Crystal Structure
Body Centered Cubic (BCC)
Body Centered Cubic (BCC)
Crystal Lattice
Atom
Number of Protons
3724
3
117
👆🏻
Number of Neutrons
4828
4
285
👆🏻
Number of Electrons
3724
3
117
👆🏻
Radius of an Atom
Atomic Radius
248.00 pm128.00 pm
0
348
👆🏻
Covalent Radius
220.00 pm139.00 pm
0
260
👆🏻
Van der Waals Radius
303.00 pm200.00 pm
0
348
👆🏻
Atomic Weight
85.47 amu52.00 amu
6.94
294
👆🏻
Atomic Volume
55.90 cm3/mol7.23 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
9.47 (-eV)170.00 (-eV)
0
392.42
👆🏻
Lattice Constant
558.50 pm291.00 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, π/2
π/2, π/2, π/2
Lattice C/A Ratio
1.591.86
0.423
1.9
👆🏻
Density
Density At Room Temperature
1.53 g/cm37.19 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
1.46 g/cm36.30 g/cm3
0.512
41
👆🏻
Tensile Strength
30.00 MPa689.00 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
0.00 (Pa)774.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
2.50 GPa115.00 GPa
1.3
222
👆🏻
Bulk Modulus
2.50 GPa160.00 GPa
0
462
👆🏻
Young's Modulus
2.40 GPa279.00 GPa
0
528
👆🏻
Poisson Ratio
0.370.21
0.032
0.47
👆🏻
Other Mechanical Properties
Ductile
-
Magnetic Characteristics
Specific Gravity
1.537.19
0.53
4500
👆🏻
Magnetic Ordering
Paramagnetic
Antiferromagnetic
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
-
Resistivity
128.00 nΩ·m125.00 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.08 106/cm Ω0.08 106/cm Ω
0
0.63
👆🏻
Electron Affinity
46.90 kJ/mol64.30 kJ/mol
0
222.8
👆🏻
Specific Heat
0.36 J/(kg K)0.45 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
31.06 J/mol·K23.35 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
58.20 W/m·K93.90 W/m·K
0
429
👆🏻
Critical Temperature
2,093.00 K1,907.00 K
26.3
3695
👆🏻
Thermal Expansion
90.00 µm/(m·K)4.90 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
69.20 kJ/mol348.80 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
2.19 kJ/mol15.31 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
82.00 kJ/mol397.50 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
76.80 J/mol.K23.80 J/mol.K
9.5
198.1
👆🏻