Calcium Holmium Comparison
Periodic Table
Symbol
Ca
Ho
Group Number
2
16
Not Available
Period Number
4
6
Block
s block
f block
Element Family
Alkaline Earth
Lanthanide
CAS Number
7440702
21
7440600
29
Space Group Name
Fm_ 3m
P63/mmc
Space Group Number
225.00
2
194.00
5
Facts
Interesting Facts
- Calcium ranks 5th rank in the list of earth’s abundance Percentage.
- It is found in the compound state.
- Gypsum or calcium sulfate is used as plaster and plaster of paris.
- Holmium metal is very soft and malleable.
- Holmium metal is well known for its corrosion resistivity.
Sources
Earth's crust, Found in Minerals, Mining, Ores of Minerals
Found in Minerals, Mining, Ores of Minerals
History
Who Discovered
Humphry Davy
Marc Delafontaine
Discovery
In 1808
In 1878
Abundance
Abundance In Universe
7 * 10-3 %
3
5 * 10-8 %
27
Abundance In Sun
~0.007 %
4
~-9999 %
Abundance In Meteorites
1.10 %
4
0.00 %
99+
Abundance In Earth's Crust
5.00 %
3
0.00 %
38
Abundance In Oceans
0.00 %
5
0.00 %
99+
Abundance In Humans
1.40 %
1
Not Available
Uses
Uses & Benefits
- It is used as a reducing agent while preparing metals like thorium and uranium. It is also used as an alloying agent for metals such as aluminum, copper & lead.
- Calcium carbonate or lime stone is used in cement.
- 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
Chemical Industry
NA
Medical Uses
Dentistry, Pharmaceutical Industry
NA
Other Uses
Alloys
Alloys, Nuclear Research
Biological Properties
Toxicity
Non Toxic
Low Toxic
Present in Human Body
Yes
No
In Blood
60.50 Blood/mg dm-3
4
Not Available
In Bone
170,000.00 p.p.m.
1
Not Available
Physical Properties
Melting Point
839.00 °C
99+
1,461.00 °C
30
Boiling Point
1,484.00 °C
99+
2,600.00 °C
99+
Appearance
Physical State
Solid
Solid
Color
Gray
Silvery White
Luster
NA
Metallic
Hardness
Mohs Hardness
1.75
17
Not Available
Brinell Hardness
170.00 MPa
99+
746.00 MPa
13
Vickers Hardness
Not Available
481.00 MPa
23
Speed of Sound
3,810.00 m/s
19
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
Ca
Ho
Isotopes
Known Isotopes
19
20
34
5
Electronegativity
Pauling Electronegativity
1.00
99+
1.23
37
Sanderson Electronegativity
0.95
24
Not Available
Allred Rochow Electronegativity
1.04
34
1.10
30
Mulliken-Jaffe Electronegativity
1.08
17
Not Available
Allen Electronegativity
1.03
39
Not Available
Electropositivity
Pauling Electropositivity
3.00
9
2.77
17
Ionization Energies
1st Energy Level
589.80 kJ/mol
99+
581.00 kJ/mol
99+
2nd Energy Level
1,145.40 kJ/mol
99+
1,140.00 kJ/mol
99+
3rd Energy Level
4,912.40 kJ/mol
7
2,204.00 kJ/mol
99+
4th Energy Level
6,491.00 kJ/mol
7
4,100.00 kJ/mol
34
5th Energy Level
8,153.00 kJ/mol
7
Not Available
6th Energy Level
10,496.00 kJ/mol
8
Not Available
7th Energy level
12,270.00 kJ/mol
12
Not Available
8th Energy Level
14,206.00 kJ/mol
15
Not Available
9th Energy Level
18,191.00 kJ/mol
12
Not Available
10th Energy Level
20,385.00 kJ/mol
16
Not Available
11th Energy Level
57,110.00 kJ/mol
3
Not Available
12th Energy Level
63,410.00 kJ/mol
3
Not Available
13th Energy Level
70,110.00 kJ/mol
3
Not Available
14th Energy Level
78,890.00 kJ/mol
4
Not Available
15th Energy Level
86,310.00 kJ/mol
5
Not Available
16th Energy Level
94,000.00 kJ/mol
6
Not Available
17th Energy Level
104,900.00 kJ/mol
7
Not Available
18th Energy Level
111,711.00 kJ/mol
8
Not Available
Electrochemical Equivalent
0.75 g/amp-hr
99+
2.02 g/amp-hr
29
Electron Work Function
2.87 eV
38
Not Available
Other Chemical Properties
Chemical Stability, Flammability, Ionization, Solubility
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
Atomic Properties
Atomic Number
20
99+
67
99+
Electron Configuration
[Ar] 4s2
[Xe] 4f11 6s2
Crystal Structure
Face Centered Cubic (FCC)
Hexagonal Close Packed (HCP)
Crystal Lattice
FCC-Crystal-Structure-of-Calcium.jpg#100
HCP-Crystal-Structure-of-Holmium.jpg#100
Atom
Number of Protons
20
99+
67
99+
Number of Neutrons
20
99+
98
34
Number of Electrons
20
99+
67
99+
Radius of an Atom
Atomic Radius
197.00 pm
6
176.00 pm
18
Covalent Radius
176.00 pm
22
192.00 pm
17
Van der Waals Radius
231.00 pm
19
216.00 pm
24
Atomic Weight
40.08 amu
99+
164.93 amu
99+
Atomic Volume
29.90 cm3/mol
7
18.70 cm3/mol
24
Adjacent Atomic Numbers
Valence Electron Potential
29.00 (-eV)
99+
47.90 (-eV)
31
Lattice Constant
558.84 pm
9
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
1.55 g/cm3
99+
8.79 g/cm3
99+
Density When Liquid (at m.p.)
1.38 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
25.50 (Pa)
3
0.00 (Pa)
16
Elasticity properties
Shear Modulus
7.40 GPa
99+
26.30 GPa
28
Bulk Modulus
17.00 GPa
99+
40.20 GPa
32
Young's Modulus
20.00 GPa
99+
64.80 GPa
31
Poisson Ratio
0.31
13
0.23
29
Other Mechanical Properties
NA
Ductile, Malleable, Sectile
Magnetic Properties
Magnetic Characteristics
Specific Gravity
4.58
99+
8.80
35
Magnetic Ordering
Diamagnetic
Paramagnetic
Electrical Properties
Electrical Property
Conductor
Conductor
Resistivity
33.60 nΩ·m
99+
814.00 nΩ·m
4
Electrical Conductivity
0.30 106/cm Ω
6
0.01 106/cm Ω
99+
Electron Affinity
2.37 kJ/mol
39
50.00 kJ/mol
21
Thermal Properties
Specific Heat
0.63 J/(kg K)
7
0.16 J/(kg K)
35
Molar Heat Capacity
25.93 J/mol·K
34
27.15 J/mol·K
19
Thermal Conductivity
201.00 W/m·K
5
16.20 W/m·K
99+
Critical Temperature
Not Available
Not Available
Thermal Expansion
22.30 µm/(m·K)
19
11.20 µm/(m·K)
35
Enthalpy
Enthalpy of Vaporization
150.00 kJ/mol
99+
241.00 kJ/mol
38
Enthalpy of Fusion
8.54 kJ/mol
99+
11.76 kJ/mol
29
Enthalpy of Atomization
184.00 kJ/mol
99+
301.00 kJ/mol
36
Standard Molar Entropy
41.60 J/mol.K
36
75.30 J/mol.K
8
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