Symbol
Fr
Nb
Group Number
15
0
17
👆🏻
Period Number
75
2
7
👆🏻
Block
s block
d block
Element Family
Alkali
Transition Metal
CAS Number
74407357440031
7429905
54386242
👆🏻
Space Group Name
-
Im_ 3m
Space Group Number
225.00229.00
11
276
👆🏻
Interesting Facts
- 223 Francium has the longest half life at 21.8.
- Francium metal is produced by alpha decay in 227Actinium 227.
- Niobium metal was used to get called Columbium in past.
- Niobium metal found freely in nature (abundance).
Sources
Formed by Decay Process, Mining
By-product of Tin Extraction, Found in Minerals, Mining, Ores of Minerals
History
Who Discovered
Marguerite Perey
Charles Hatchett
Discovery
In 1939
In 1801
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
0.00 %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
- Francium has no known uses as it has a half life of only 22 minutes.
- Niobium alloys are used in jet engines and rockets and spacecraft, beams and girders for buildings and oil and gas pipelines.
- It is used superconducting magnets in particles accelerators, NMR and MRI equipment.
Industrial Uses
-
Aerospace Industry, Ammunition Industry, Electrical Industry, Electronic Industry
Medical Uses
-
-
Other Uses
-
Alloys
Biological Properties
Toxicity
-
Low Toxic
Present in Human Body
✔
✘
✔
✘
In Blood
0.00 Blood/mg dm-30.01 Blood/mg dm-3
0
1970
👆🏻
In Bone
0.00 p.p.m.0.07 p.p.m.
0
170000
👆🏻
Melting Point
27.00 °C2,468.00 °C
-38.83
3410
👆🏻
Boiling Point
677.00 °C2,468.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
-
Gray
Luster
-
Metallic
Hardness
Mohs Hardness
0.206.00
0.2
8.5
👆🏻
Brinell Hardness
119.00 MPa735.00 MPa
0.14
3490
👆🏻
Vickers Hardness
300.00 MPa870.00 MPa
0
3920
👆🏻
Speed of Sound
2,440.00 m/s3,480.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.702.30
0.155
3.41
👆🏻
Reflectivity
72.00 %70.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Fr
Nb
Isotopes
Known Isotopes
3317
0
38
👆🏻
Electronegativity
Pauling Electronegativity
0.701.60
0
2.6
👆🏻
Sanderson Electronegativity
0.701.42
0.22
2.56
👆🏻
Allred Rochow Electronegativity
0.861.23
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
0.681.60
0.62
2.48
👆🏻
Allen Electronegativity
0.671.41
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
3.302.40
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
380.00 kJ/mol652.10 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
392.80 kJ/mol1,380.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
392.80 kJ/mol2,416.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
392.80 kJ/mol3,700.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
392.00 kJ/mol4,877.00 kJ/mol
392
97510
👆🏻
6th Energy Level
3,920.00 kJ/mol9,847.00 kJ/mol
1007
105800
👆🏻
7th Energy level
3,920.00 kJ/mol12,100.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
3,920.00 kJ/mol6,520.00 kJ/mol
730
125300
👆🏻
9th Energy Level
3,920.00 kJ/mol5,470.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
392.00 kJ/mol5,470.00 kJ/mol
392
144300
👆🏻
11th Energy Level
392.00 kJ/mol6,520.00 kJ/mol
392
169988
👆🏻
12th Energy Level
38,000.00 kJ/mol6,520.00 kJ/mol
0
189368
👆🏻
13th Energy Level
3,920.00 kJ/mol5,470.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
380.00 kJ/mol691.00 kJ/mol
380
86450
👆🏻
15th Energy Level
67,700.00 kJ/mol65,200.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
39,200.00 kJ/mol652.10 kJ/mol
375.7
109480
👆🏻
17th Energy Level
392.00 kJ/mol652.10 kJ/mol
375.7
122200
👆🏻
18th Energy Level
3,920.00 kJ/mol6,520.00 kJ/mol
0
134810
👆🏻
19th Energy Level
392.80 kJ/mol652.10 kJ/mol
375.7
148700
👆🏻
20th Energy Level
392.00 kJ/mol652.00 kJ/mol
0
171200
👆🏻
21st Energy Level
392.00 kJ/mol652.10 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
392.00 kJ/mol694.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
392.80 kJ/mol4,490.00 kJ/mol
357.6
198800
👆🏻
24th Energy Level
392.00 kJ/mol652.10 kJ/mol
297.3
195200
👆🏻
25th Energy Level
392.00 kJ/mol652.10 kJ/mol
0
121900
👆🏻
26th Energy Level
392.80 kJ/mol652.10 kJ/mol
357.6
127700
👆🏻
27th Energy Level
392.00 kJ/mol652.10 kJ/mol
0
133800
👆🏻
28th Energy Level
380.00 kJ/mol652.10 kJ/mol
297.3
139800
👆🏻
29th Energy Level
392.00 kJ/mol652.10 kJ/mol
0
148100
👆🏻
30th Energy Level
677.00 kJ/mol652.00 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
8.32 g/amp-hr0.69 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
4.07 eV4.30 eV
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
Atomic Number
8741
3
117
👆🏻
Electron Configuration
[Rn] 7s1
[Kr] 4d4 5s1
Crystal Structure
Body Centered Cubic (BCC)
Body Centered Cubic (BCC)
Crystal Lattice
Atom
Number of Protons
8741
3
117
👆🏻
Number of Neutrons
13652
4
285
👆🏻
Number of Electrons
8741
3
117
👆🏻
Radius of an Atom
Atomic Radius
348.00 pm146.00 pm
0
348
👆🏻
Covalent Radius
260.00 pm164.00 pm
0
260
👆🏻
Van der Waals Radius
348.00 pm200.00 pm
0
348
👆🏻
Atomic Weight
223.00 amu92.91 amu
6.94
294
👆🏻
Atomic Volume
71.00 cm3/mol10.87 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
8.00 (-eV)104.00 (-eV)
0
392.42
👆🏻
Lattice Constant
440.00 pm330.04 pm
0
891.25
👆🏻
Lattice Angles
-
π/2, π/2, π/2
Lattice C/A Ratio
1.561.47
0.423
1.9
👆🏻
Density
Density At Room Temperature
1.87 g/cm38.57 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
1.87 g/cm38.57 g/cm3
0.512
41
👆🏻
Tensile Strength
50.00 MPa330.00 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)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
3.60 GPa38.00 GPa
1.3
222
👆🏻
Bulk Modulus
6.00 GPa170.00 GPa
0
462
👆🏻
Young's Modulus
0.00 GPa105.00 GPa
0
528
👆🏻
Poisson Ratio
0.440.40
0.032
0.47
👆🏻
Other Mechanical Properties
-
Ductile, Malleable
Magnetic Characteristics
Specific Gravity
0.878.57
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
Poor Conductor
Conductor
Resistivity
3.00 nΩ·m152.00 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.03 106/cm Ω0.07 106/cm Ω
0
0.63
👆🏻
Electron Affinity
0.70 kJ/mol86.10 kJ/mol
0
222.8
👆🏻
Specific Heat
0.15 J/(kg K)0.26 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
27.00 J/mol·K24.60 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
15.00 W/m·K53.70 W/m·K
0
429
👆🏻
Critical Temperature
300.00 K2,750.00 K
26.3
3695
👆🏻
Thermal Expansion
18.90 µm/(m·K)7.30 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
67.00 kJ/mol696.60 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
2.30 kJ/mol27.20 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
71.00 kJ/mol745.00 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
42.00 J/mol.K36.40 J/mol.K
9.5
198.1
👆🏻