Strontium Holmium Comparison
Periodic Table
Symbol
Sr
Ho
Group Number
2
16
Not Available
Period Number
5
6
Block
s block
f block
Element Family
Alkaline Earth
Lanthanide
CAS Number
7440246
99+
7440600
29
Space Group Name
Fm_ 3m
P63/mmc
Space Group Number
225.00
2
194.00
5
Facts
Interesting Facts
- Strontium element is softer than Calcium.
- Silvery Strontium turns yellow, if exposed to air.
- Holmium metal is very soft and malleable.
- Holmium metal is well known for its corrosion resistivity.
Sources
Found in Minerals, Mining, Ores of Minerals
Found in Minerals, Mining, Ores of Minerals
History
Who Discovered
William Cruickshank
Marc Delafontaine
Discovery
In 1787
In 1878
Abundance
Abundance In Universe
4 * 10-6 %
14
5 * 10-8 %
27
Abundance In Sun
~0.000005 %
15
~-9999 %
Abundance In Meteorites
0.00 %
15
0.00 %
99+
Abundance In Earth's Crust
0.04 %
10
0.00 %
38
Abundance In Oceans
0.00 %
4
0.00 %
99+
Abundance In Humans
0.00 %
7
Not Available
Uses
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.
- Holmium metal has an ability to absorb neutrons, so this metal is used in nuclear reactors to keep the chain reactions of elements under control.
- Alloys of Holmium are used to produce Magnet.
Industrial Uses
Ammunition Industry, Chemical Industry
NA
Medical Uses
NA
NA
Other Uses
Alloys
Alloys, Nuclear Research
Biological Properties
Toxicity
Non Toxic
Low Toxic
Present in Human Body
Yes
No
In Blood
0.03 Blood/mg dm-3
19
Not Available
In Bone
140.00 p.p.m.
7
Not Available
Physical Properties
Melting Point
769.00 °C
99+
1,461.00 °C
30
Boiling Point
1,384.00 °C
99+
2,600.00 °C
99+
Appearance
Physical State
Solid
Solid
Color
Silvery White
Silvery White
Luster
Metallic
Metallic
Hardness
Mohs Hardness
1.50
18
Not Available
Brinell Hardness
Not Available
746.00 MPa
13
Vickers Hardness
Not Available
481.00 MPa
23
Speed of Sound
Not Available
2,760.00 m/s
30
Optical Properties
Allotropes
No
No
α Allotropes
Not Available
Not Available
β Allotropes
Not Available
Not Available
γ Allotropes
Not Available
Not Available
Chemical Properties
Chemical Formula
Sr
Ho
Isotopes
Known Isotopes
27
12
34
5
Electronegativity
Pauling Electronegativity
0.95
99+
1.23
37
Sanderson Electronegativity
0.72
27
Not Available
Allred Rochow Electronegativity
0.99
37
1.10
30
Mulliken-Jaffe Electronegativity
1.00
18
Not Available
Allen Electronegativity
0.96
40
Not Available
Electropositivity
Pauling Electropositivity
3.05
7
2.77
17
Ionization Energies
1st Energy Level
549.50 kJ/mol
99+
581.00 kJ/mol
99+
2nd Energy Level
1,064.20 kJ/mol
99+
1,140.00 kJ/mol
99+
3rd Energy Level
4,138.00 kJ/mol
10
2,204.00 kJ/mol
99+
4th Energy Level
5,500.00 kJ/mol
13
4,100.00 kJ/mol
34
5th Energy Level
6,910.00 kJ/mol
18
Not Available
6th Energy Level
8,760.00 kJ/mol
18
Not Available
7th Energy level
10,230.00 kJ/mol
19
Not Available
8th Energy Level
11,800.00 kJ/mol
19
Not Available
9th Energy Level
15,600.00 kJ/mol
17
Not Available
10th Energy Level
17,100.00 kJ/mol
19
Not Available
11th Energy Level
31,270.00 kJ/mol
6
Not Available
Electrochemical Equivalent
1.64 g/amp-hr
99+
2.02 g/amp-hr
29
Electron Work Function
2.59 eV
99+
Not Available
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
Atomic Properties
Atomic Number
38
99+
67
99+
Electron Configuration
[Kr] 5s2
[Xe] 4f11 6s2
Crystal Structure
Face Centered Cubic (FCC)
Hexagonal Close Packed (HCP)
Crystal Lattice
FCC-Crystal-Structure-of-Strontium.jpg#100
HCP-Crystal-Structure-of-Holmium.jpg#100
Atom
Number of Protons
38
99+
67
99+
Number of Neutrons
50
99+
98
34
Number of Electrons
38
99+
67
99+
Radius of an Atom
Atomic Radius
215.00 pm
5
176.00 pm
18
Covalent Radius
195.00 pm
15
192.00 pm
17
Van der Waals Radius
249.00 pm
7
216.00 pm
24
Atomic Weight
87.62 amu
99+
164.93 amu
99+
Atomic Volume
33.70 cm3/mol
6
18.70 cm3/mol
24
Adjacent Atomic Numbers
Valence Electron Potential
25.70 (-eV)
99+
47.90 (-eV)
31
Lattice Constant
608.49 pm
6
357.73 pm
38
Lattice Angles
π/2, π/2, π/2
π/2, π/2, 2 π/3
Lattice C/A Ratio
Not Available
1.57
17
Mechanical Properties
Density
Density At Room Temperature
2.64 g/cm3
99+
8.79 g/cm3
99+
Density When Liquid (at m.p.)
2.38 g/cm3
99+
8.34 g/cm3
26
Tensile Strength
Not Available
Not Available
Viscosity
Not Available
Not Available
Vapor Pressure
Vapor Pressure at 1000 K
121.00 (Pa)
1
0.00 (Pa)
16
Elasticity properties
Shear Modulus
6.03 GPa
99+
26.30 GPa
28
Bulk Modulus
Not Available
40.20 GPa
32
Young's Modulus
15.70 GPa
99+
64.80 GPa
31
Poisson Ratio
0.28
17
0.23
29
Other Mechanical Properties
NA
Ductile, Malleable, Sectile
Magnetic Properties
Magnetic Characteristics
Specific Gravity
2.64
99+
8.80
35
Magnetic Ordering
Paramagnetic
Paramagnetic
Electrical Properties
Electrical Property
NA
Conductor
Resistivity
132.00 nΩ·m
24
814.00 nΩ·m
4
Electrical Conductivity
0.08 106/cm Ω
26
0.01 106/cm Ω
99+
Electron Affinity
5.03 kJ/mol
38
50.00 kJ/mol
21
Thermal Properties
Specific Heat
0.30 J/(kg K)
18
0.16 J/(kg K)
35
Molar Heat Capacity
26.40 J/mol·K
28
27.15 J/mol·K
19
Thermal Conductivity
35.40 W/m·K
37
16.20 W/m·K
99+
Critical Temperature
Not Available
Not Available
Thermal Expansion
22.50 µm/(m·K)
18
11.20 µm/(m·K)
35
Enthalpy
Enthalpy of Vaporization
150.00 kJ/mol
99+
241.00 kJ/mol
38
Enthalpy of Fusion
9.16 kJ/mol
38
11.76 kJ/mol
29
Enthalpy of Atomization
163.20 kJ/mol
99+
301.00 kJ/mol
36
Standard Molar Entropy
55.00 J/mol.K
26
75.30 J/mol.K
8
|
||
|
||
|
