Americium Thorium Comparison
Periodic Table
Symbol
Am
Th
Group Number
Not Available
0
18
Period Number
7
7
Block
f block
f block
Element Family
Actinide
Actinide
CAS Number
7440359
99+
7440326
99+
Space Group Name
P63/mmc
P63/mmc
Space Group Number
194.00
5
194.00
5
Facts
Interesting Facts
- Americium metal is produced by bombarding Plutonium with Neutrons.
- Americium metal was discovered as a by-product while testing an atomic bomb (Manhattan Project).
- Thorium metal is used as an alternate option over Uranium for nuclear fuel.
- Thorium metals appearance (silvery white, soft) is somewhat similar to Lead metal.
Sources
Obtained By Bombarding Plutonium with Neutrons
Found in Minerals, Mining
History
Who Discovered
Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, Albert Ghiorso
Jöns Jakob Berzelius
Discovery
In 1944
In 1829
Abundance
Abundance In Universe
Not Available
3 * 10-4 %
9
Abundance In Sun
~-9999 %
~0.0004 %
9
Abundance In Meteorites
Not Available
0.05 %
11
Abundance In Earth's Crust
Not Available
0.66 %
7
Abundance In Oceans
Not Available
0.00 %
15
Uses
Uses & Benefits
- Americium metal is used in smoke detection alarms.
- In the future, this metal has a potential to be used in batteries of spacecrafts.
- Thorium metal is used as an allying agent for Magnesium, It imparts greater strength and resistance to temperature.
- compound of this metal Thorium oxide is used as an industrial catalyst.
Industrial Uses
NA
Aerospace Industry, Automobile Industry, Chemical Industry, Electrical Industry, Electronic Industry
Medical Uses
NA
Dentistry, Surgical Instruments Manufacturing
Other Uses
Alloys, Nuclear Research, Research Purposes
Alloys, Jewellery, Sculptures, Statues
Biological Properties
Toxicity
Toxic
Non Toxic
Present in Human Body
No
Yes
In Blood
0.00 Blood/mg dm-3
37
0.00 Blood/mg dm-3
33
In Bone
0.00 p.p.m.
36
0.02 p.p.m.
29
Physical Properties
Melting Point
994.00 °C
99+
1,750.00 °C
17
Boiling Point
2,607.00 °C
99+
4,790.00 °C
8
Appearance
Physical State
Solid
Solid
Color
Silvery White
Silver
Luster
NA
NA
Hardness
Mohs Hardness
Not Available
3.00
12
Brinell Hardness
Not Available
390.00 MPa
29
Vickers Hardness
Not Available
295.00 MPa
29
Speed of Sound
Not Available
2,490.00 m/s
36
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
Am
Th
Isotopes
Known Isotopes
16
23
28
11
Electronegativity
Pauling Electronegativity
1.30
32
1.30
32
Allred Rochow Electronegativity
1.20
27
1.11
29
Electropositivity
Pauling Electropositivity
2.70
22
2.70
22
Ionization Energies
1st Energy Level
578.00 kJ/mol
99+
587.00 kJ/mol
99+
2nd Energy Level
1,158.00 kJ/mol
99+
1,110.00 kJ/mol
99+
3rd Energy Level
2,132.00 kJ/mol
99+
1,978.00 kJ/mol
99+
4th Energy Level
3,493.00 kJ/mol
99+
2,780.00 kJ/mol
99+
Electrochemical Equivalent
3.02 g/amp-hr
17
2.16 g/amp-hr
24
Electron Work Function
Not Available
3.41 eV
32
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity, Solubility
Corrosion, Ionization, Radioactive Isotopes, Radioactivity
Atomic Properties
Atomic Number
95
23
90
28
Electron Configuration
[Rn] 5f7 7s2
[Rn] 6d2 7s2
Crystal Structure
Double Hexagonal Close Packed (DHCP)
Face Centered Cubic (FCC)
Crystal Lattice
DHCP-Crystal-Structure-of-Americium.jpg#100
FCC-Crystal-Structure-of-Thorium.jpg#100
Atom
Number of Protons
95
23
90
28
Number of Neutrons
148
12
142
15
Number of Electrons
95
23
90
28
Radius of an Atom
Atomic Radius
173.00 pm
21
179.80 pm
15
Covalent Radius
180.00 pm
21
206.00 pm
7
Van der Waals Radius
244.00 pm
10
237.00 pm
15
Atomic Weight
243.00 amu
20
232.04 amu
23
Atomic Volume
17.86 cm3/mol
29
19.90 cm3/mol
20
Adjacent Atomic Numbers
Valence Electron Potential
44.00 (-eV)
40
59.30 (-eV)
23
Lattice Constant
346.81 pm
99+
508.42 pm
14
Lattice Angles
π/2, π/2, 2 π/3
π/2, π/2, π/2
Lattice C/A Ratio
Not Available
Not Available
Mechanical Properties
Density
Density At Room Temperature
12.00 g/cm3
30
11.72 g/cm3
32
Tensile Strength
Not Available
Not Available
Viscosity
Not Available
Not Available
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)
13
Not Available
Vapor Pressure at 2000 K
Not Available
0.00 (Pa)
22
Elasticity properties
Shear Modulus
Not Available
31.00 GPa
21
Bulk Modulus
Not Available
54.00 GPa
22
Young's Modulus
Not Available
79.00 GPa
24
Poisson Ratio
Not Available
0.27
20
Other Mechanical Properties
NA
Ductile
Magnetic Properties
Magnetic Characteristics
Specific Gravity
13.67
15
11.70
23
Magnetic Ordering
Paramagnetic
Paramagnetic
Electrical Properties
Electrical Property
Unknown
Superconductor
Resistivity
0.69 nΩ·m
99+
157.00 nΩ·m
22
Electrical Conductivity
0.02 106/cm Ω
99+
0.07 106/cm Ω
31
Thermal Properties
Specific Heat
0.11 J/(kg K)
99+
0.12 J/(kg K)
40
Molar Heat Capacity
62.70 J/mol·K
1
26.23 J/mol·K
30
Thermal Conductivity
10.00 W/m·K
99+
54.00 W/m·K
28
Critical Temperature
Not Available
Not Available
Thermal Expansion
Not Available
11.00 µm/(m·K)
36
Enthalpy
Enthalpy of Vaporization
Not Available
429.00 kJ/mol
15
Enthalpy of Fusion
14.39 kJ/mol
24
15.48 kJ/mol
19
Enthalpy of Atomization
268.00 kJ/mol
40
468.60 kJ/mol
15
Standard Molar Entropy
Not Available
27.30 J/mol.K
99+
|
||
|
||
|
