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Chromium Americium Comparison


Americium Chromium comparison


Periodic Table

Symbol
Cr   
Am   

Group Number
6   
12
Not Available   

Period Number
4   
7   

Block
d block   
f block   

Element Family
Transition Metal   
Actinide   

CAS Number
7440473   
39
7440359   
99+

Space Group Name
Im_ 3m   
P63/mmc   

Space Group Number
229.00   
1
194.00   
5

Facts

Interesting Facts
  • Chromium is highly reactive, hence it is not found free in nature.
  • Ores of Chromites mineral are the major source of Chromium metal.
  • Almost 90% leather tanning is done with the help of chromium.
  
  • Americium metal is produced by bombarding Plutonium with Neutrons.
  • Americium metal was discovered as a by-product while testing an atomic bomb (Manhattan Project).
  

Sources
Found in Minerals, Mining, Ores of metals, Ores of Minerals   
Obtained By Bombarding Plutonium with Neutrons   

History
  
  

Who Discovered
Louis Nicolas Vauquelin   
Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, Albert Ghiorso   

Discovery
In Between 1797 - 1798   
In 1944   

Abundance
  
  

Abundance In Universe
1.5 * 10-3 %   
7
Not Available   

Abundance In Sun
~0.002 %   
7
~-9999 %   

Abundance In Meteorites
0.30 %   
7
Not Available   

Abundance In Earth's Crust
0.01 %   
13
Not Available   

Abundance In Oceans
0.00 %   
16
Not Available   

Abundance In Humans
0.00 %   
16
Not Available   

Uses

Uses & Benefits
  • It is used to harden the steel and produces a stainless steel and other various alloys.
  • It is also used to give proper finish to polished mirrors. Its chromium plates are used in bathroom fittings.
  
  • Americium metal is used in smoke detection alarms.
  • In the future, this metal has a potential to be used in batteries of spacecrafts.
  

Industrial Uses
Automobile Industry, Chemical Industry   
NA   

Medical Uses
NA   
NA   

Other Uses
Alloys   
Alloys, Nuclear Research, Research Purposes   

Biological Properties
  
  

Toxicity
Highly Toxic   
Toxic   

Present in Human Body
Yes   
No   

In Blood
0.11 Blood/mg dm-3   
12
0.00 Blood/mg dm-3   
37

In Bone
0.33 p.p.m.   
21
0.00 p.p.m.   
36

Physical Properties

Melting Point
1,857.00 °C   
14
994.00 °C   
99+

Boiling Point
2,672.00 °C   
39
2,607.00 °C   
99+

Appearance
  
  

Physical State
Solid   
Solid   

Color
Silver   
Silvery White   

Luster
Metallic   
NA   

Hardness
  
  

Mohs Hardness
8.50   
1
Not Available   

Brinell Hardness
687.00 MPa   
16
Not Available   

Vickers Hardness
1,060.00 MPa   
10
Not Available   

Speed of Sound
5,940.00 m/s   
5
Not Available   

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
Cr   
Am   

Isotopes
  
  

Known Isotopes
21   
18
16   
23

Electronegativity
  
  

Pauling Electronegativity
1.66   
18
1.30   
32

Sanderson Electronegativity
1.66   
14
Not Available   

Allred Rochow Electronegativity
1.56   
10
1.20   
27

Allen Electronegativity
1.65   
19
Not Available   

Electropositivity
  
  

Pauling Electropositivity
2.34   
36
2.70   
22

Ionization Energies
  
  

1st Energy Level
26,130.00 kJ/mol   
1
578.00 kJ/mol   
99+

2nd Energy Level
28,750.00 kJ/mol   
1
1,158.00 kJ/mol   
99+

3rd Energy Level
34,230.00 kJ/mol   
1
2,132.00 kJ/mol   
99+

4th Energy Level
37,066.00 kJ/mol   
1
3,493.00 kJ/mol   
99+

5th Energy Level
97,510.00 kJ/mol   
1
Not Available   

6th Energy Level
105,800.00 kJ/mol   
1
Not Available   

7th Energy level
114,300.00 kJ/mol   
1
Not Available   

8th Energy Level
125,300.00 kJ/mol   
1
Not Available   

9th Energy Level
134,700.00 kJ/mol   
1
Not Available   

10th Energy Level
144,300.00 kJ/mol   
1
Not Available   

11th Energy Level
26,130.00 kJ/mol   
12
Not Available   

12th Energy Level
28,750.00 kJ/mol   
13
Not Available   

13th Energy Level
34,230.00 kJ/mol   
10
Not Available   

14th Energy Level
37,066.00 kJ/mol   
12
Not Available   

15th Energy Level
97,510.00 kJ/mol   
1
Not Available   

16th Energy Level
105,800.00 kJ/mol   
2
Not Available   

17th Energy Level
114,300.00 kJ/mol   
3
Not Available   

18th Energy Level
125,300.00 kJ/mol   
4
Not Available   

19th Energy Level
134,700.00 kJ/mol   
5
Not Available   

20th Energy Level
144,300.00 kJ/mol   
7
Not Available   

21st Energy Level
157,700.00 kJ/mol   
7
Not Available   

22nd Energy Level
166,090.00 kJ/mol   
6
Not Available   

Electrochemical Equivalent
0.32 g/amp-hr   
99+
3.02 g/amp-hr   
17

Electron Work Function
4.50 eV   
14
Not Available   

Other Chemical Properties
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility   
Ionization, Radioactive Isotopes, Radioactivity, Solubility   

Atomic Properties

Atomic Number
24   
99+
95   
23

Electron Configuration
[Ar] 3d5 4s1   
[Rn] 5f7 7s2   

Crystal Structure
Body Centered Cubic (BCC)   
Double Hexagonal Close Packed (DHCP)   

Crystal Lattice
BCC-Crystal-Structure-.jpg#100   
DHCP-Crystal-Structure-of-Americium.jpg#100   

Atom
  
  

Number of Protons
24   
99+
95   
23

Number of Neutrons
28   
99+
148   
12

Number of Electrons
24   
99+
95   
23

Radius of an Atom
  
  

Atomic Radius
128.00 pm   
99+
173.00 pm   
21

Covalent Radius
139.00 pm   
99+
180.00 pm   
21

Van der Waals Radius
200.00 pm   
28
244.00 pm   
10

Atomic Weight
52.00 amu   
99+
243.00 amu   
20

Atomic Volume
7.23 cm3/mol   
99+
17.86 cm3/mol   
29

Adjacent Atomic Numbers
  
  

Previous Element
Vanadium
  
Plutonium
  

Next Element
Manganese
  
Curium
  

Valence Electron Potential
170.00 (-eV)   
4
44.00 (-eV)   
40

Lattice Constant
291.00 pm   
99+
346.81 pm   
99+

Lattice Angles
π/2, π/2, π/2   
π/2, π/2, 2 π/3   

Lattice C/A Ratio
Not Available   
Not Available   

Mechanical Properties

Density
  
  

Density At Room Temperature
7.19 g/cm3   
99+
12.00 g/cm3   
30

Density When Liquid (at m.p.)
6.30 g/cm3   
40
Not Available   

Tensile Strength
689.00 MPa   
7
Not Available   

Viscosity
Not Available   
Not Available   

Vapor Pressure
  
  

Vapor Pressure at 1000 K
0.00 (Pa)   
24
0.00 (Pa)   
13

Vapor Pressure at 2000 K
774.00 (Pa)   
1
Not Available   

Elasticity properties
  
  

Shear Modulus
115.00 GPa   
9
Not Available   

Bulk Modulus
160.00 GPa   
11
Not Available   

Young's Modulus
279.00 GPa   
8
Not Available   

Poisson Ratio
0.21   
32
Not Available   

Other Mechanical Properties
NA   
NA   

Magnetic Properties

Magnetic Characteristics
  
  

Specific Gravity
7.19   
99+
13.67   
15

Magnetic Ordering
Antiferromagnetic   
Paramagnetic   

Electrical Properties
  
  

Electrical Property
NA   
Unknown   

Resistivity
125.00 nΩ·m   
27
0.69 nΩ·m   
99+

Electrical Conductivity
0.08 106/cm Ω   
25
0.02 106/cm Ω   
99+

Electron Affinity
64.30 kJ/mol   
15
Not Available   

Thermal Properties

Specific Heat
0.45 J/(kg K)   
12
0.11 J/(kg K)   
99+

Molar Heat Capacity
23.35 J/mol·K   
99+
62.70 J/mol·K   
1

Thermal Conductivity
93.90 W/m·K   
17
10.00 W/m·K   
99+

Critical Temperature
Not Available   
Not Available   

Thermal Expansion
4.90 µm/(m·K)   
99+
Not Available   

Enthalpy
  
  

Enthalpy of Vaporization
348.80 kJ/mol   
24
Not Available   

Enthalpy of Fusion
15.31 kJ/mol   
20
14.39 kJ/mol   
24

Enthalpy of Atomization
397.50 kJ/mol   
21
268.00 kJ/mol   
40

Standard Molar Entropy
23.80 J/mol.K   
99+
Not Available   

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