Symbol
Sr
Fm
Group Number
23
0
17
👆🏻
Period Number
57
2
7
👆🏻
Block
s block
f block
Element Family
Alkaline Earth
Actinide
CAS Number
74402467440724
7429905
54386242
👆🏻
Space Group Name
Fm_ 3m
-
Space Group Number
225.00194.00
11
276
👆🏻
Interesting Facts
- Strontium element is softer than Calcium.
- Silvery Strontium turns yellow, if exposed to air.
- Fermium metal is highly radioactive in nature.
- Fermium is synthetically produced metal.
Sources
Found in Minerals, Mining, Ores of Minerals
Bombarding Pu-239 with Neutrons
History
Who Discovered
William Cruickshank
Lawrence Berkeley National Laboratory
Discovery
In 1787
In 1952
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
0.04 %0.00 %
1E-37
8.1
👆🏻
Abundance In Oceans
0.00 %-
0
1.1
👆🏻
Abundance In Humans
0.00 %-
0
1.4
👆🏻
Uses & Benefits
- Strontium metal is used to producing ferrite magnets as well as refining zinc.
-
By-product of nuclear reactors called Strontium-90 is a radioactive isotope; it is absorbed by tissues and destroys bone marrow and cancer growth.
- Currently known uses of Fermium metal are limited to research purpose only.
Industrial Uses
Ammunition Industry, Chemical Industry
-
Medical Uses
-
-
Other Uses
Alloys
-
Biological Properties
Toxicity
Non Toxic
-
Present in Human Body
✔
✘
✔
✘
In Blood
0.03 Blood/mg dm-30.00 Blood/mg dm-3
0
1970
👆🏻
In Bone
140.00 p.p.m.0.00 p.p.m.
0
170000
👆🏻
Melting Point
769.00 °C1,527.00 °C
-38.83
3410
👆🏻
Boiling Point
1,384.00 °C0.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery White
-
Luster
Metallic
-
Hardness
Mohs Hardness
1.506.00
0.2
8.5
👆🏻
Brinell Hardness
110.00 MPa500.00 MPa
0.14
3490
👆🏻
Vickers Hardness
15.00 MPa600.00 MPa
0
3920
👆🏻
Speed of Sound
4,170.00 m/s2,500.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.431.30
0.155
3.41
👆🏻
Reflectivity
65.00 %59.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Sr
Fm
Isotopes
Known Isotopes
2718
0
38
👆🏻
Electronegativity
Pauling Electronegativity
0.951.30
0
2.6
👆🏻
Sanderson Electronegativity
0.721.30
0.22
2.56
👆🏻
Allred Rochow Electronegativity
0.991.20
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.001.30
0.62
2.48
👆🏻
Allen Electronegativity
0.961.30
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
3.052.70
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
549.50 kJ/mol627.00 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
1,064.20 kJ/mol1,225.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
4,138.00 kJ/mol2,363.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
5,500.00 kJ/mol3,792.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
6,910.00 kJ/mol6,270.00 kJ/mol
392
97510
👆🏻
6th Energy Level
8,760.00 kJ/mol6,270.00 kJ/mol
1007
105800
👆🏻
7th Energy level
10,230.00 kJ/mol6,270.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
11,800.00 kJ/mol6,270.00 kJ/mol
730
125300
👆🏻
9th Energy Level
15,600.00 kJ/mol7,040.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
17,100.00 kJ/mol6,270.00 kJ/mol
392
144300
👆🏻
11th Energy Level
31,270.00 kJ/mol6,270.00 kJ/mol
392
169988
👆🏻
12th Energy Level
5,490.00 kJ/mol62,700.00 kJ/mol
0
189368
👆🏻
13th Energy Level
5,490.00 kJ/mol6,270.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
5,490.00 kJ/mol6,270.00 kJ/mol
380
86450
👆🏻
15th Energy Level
54,900.00 kJ/mol62,700.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
54,900.00 kJ/mol62,700.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
549.50 kJ/mol627.00 kJ/mol
375.7
122200
👆🏻
18th Energy Level
5,490.00 kJ/mol6,270.00 kJ/mol
0
134810
👆🏻
19th Energy Level
549.50 kJ/mol994.80 kJ/mol
375.7
148700
👆🏻
20th Energy Level
549.00 kJ/mol627.00 kJ/mol
0
171200
👆🏻
21st Energy Level
549.50 kJ/mol627.00 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
549.00 kJ/mol345.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
549.50 kJ/mol6,270.00 kJ/mol
357.6
198800
👆🏻
24th Energy Level
549.50 kJ/mol627.60 kJ/mol
297.3
195200
👆🏻
25th Energy Level
549.00 kJ/mol627.00 kJ/mol
0
121900
👆🏻
26th Energy Level
549.50 kJ/mol627.60 kJ/mol
357.6
127700
👆🏻
27th Energy Level
549.50 kJ/mol627.60 kJ/mol
0
133800
👆🏻
28th Energy Level
549.50 kJ/mol627.60 kJ/mol
297.3
139800
👆🏻
29th Energy Level
549.50 kJ/mol627.60 kJ/mol
0
148100
👆🏻
30th Energy Level
549.50 kJ/mol627.60 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
1.64 g/amp-hr3.20 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
2.59 eV4.47 eV
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
Ionization, Radioactive Isotopes, Radioactivity
Atomic Number
38100
3
117
👆🏻
Electron Configuration
[Kr] 5s2
[Rn] 5f12 7s2
Crystal Structure
Face Centered Cubic (FCC)
Not Known
Crystal Lattice
Atom
Number of Protons
38100
3
117
👆🏻
Number of Neutrons
50157
4
285
👆🏻
Number of Electrons
38100
3
117
👆🏻
Radius of an Atom
Atomic Radius
215.00 pm180.00 pm
0
348
👆🏻
Covalent Radius
195.00 pm180.00 pm
0
260
👆🏻
Van der Waals Radius
249.00 pm245.00 pm
0
348
👆🏻
Atomic Weight
87.62 amu257.00 amu
6.94
294
👆🏻
Atomic Volume
33.70 cm3/mol18.00 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
25.70 (-eV)0.00 (-eV)
0
392.42
👆🏻
Lattice Constant
608.49 pm350.00 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, π/2
-
Lattice C/A Ratio
1.571.63
0.423
1.9
👆🏻
Density
Density At Room Temperature
2.64 g/cm39.70 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
2.38 g/cm39.70 g/cm3
0.512
41
👆🏻
Tensile Strength
170.00 MPa0.10 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
121.00 (Pa)0.00 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
0.00 (Pa)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
6.03 GPa30.00 GPa
1.3
222
👆🏻
Bulk Modulus
11.00 GPa50.00 GPa
0
462
👆🏻
Young's Modulus
15.70 GPa0.00 GPa
0
528
👆🏻
Poisson Ratio
0.280.35
0.032
0.47
👆🏻
Other Mechanical Properties
-
-
Magnetic Characteristics
Specific Gravity
2.649.70
0.53
4500
👆🏻
Magnetic Ordering
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
-
-
Resistivity
132.00 nΩ·m7.90 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.08 106/cm Ω0.00 106/cm Ω
0
0.63
👆🏻
Electron Affinity
5.03 kJ/mol0.00 kJ/mol
0
222.8
👆🏻
Specific Heat
0.30 J/(kg K)0.10 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
26.40 J/mol·K27.00 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
35.40 W/m·K0.00 W/m·K
0
429
👆🏻
Critical Temperature
1,050.00 K1,323.00 K
26.3
3695
👆🏻
Thermal Expansion
22.50 µm/(m·K)11.00 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
150.00 kJ/mol319.20 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
9.16 kJ/mol13.30 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
163.20 kJ/mol-
61.5
837
👆🏻
Standard Molar Entropy
55.00 J/mol.K50.00 J/mol.K
9.5
198.1
👆🏻