Zinc Chromium Comparison
Periodic Table
Symbol
Zn
Cr
Group Number
12
6
6
12
Period Number
4
4
Block
d block
d block
Element Family
Transition Metal
Transition Metal
CAS Number
7440666
24
7440473
39
Space Group Name
P63/mmc
Im_ 3m
Space Group Number
194.00
5
229.00
1
Facts
Interesting Facts
- Zinc metal found (obtain) in many forms like granules, foil, dust and in a powder form.
- The leading producers of Zinc metal are Australia, Canada, China, U.S.A and Peru.
- 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.
Sources
Earth's crust, Found in Minerals, Mining, Ores of Minerals
Found in Minerals, Mining, Ores of metals, Ores of Minerals
History
Who Discovered
Indian metallurgists
Louis Nicolas Vauquelin
Discovery
Before 1000 BCE
In Between 1797 - 1798
Abundance
Abundance In Universe
3 * 10-5 %
11
1.5 * 10-3 %
7
Abundance In Sun
~0.0002 %
10
~0.002 %
7
Abundance In Meteorites
0.02 %
12
0.30 %
7
Abundance In Earth's Crust
0.01 %
16
0.01 %
13
Abundance In Oceans
0.00 %
10
0.00 %
16
Abundance In Humans
0.00 %
6
0.00 %
16
Uses
Uses & Benefits
- It is mainly used for Galvanizing other metals.
- It is also used for manufacturing die-casting and it is very essential for automobile industry.
- 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.
Industrial Uses
Electrical Industry, Electronic Industry
Automobile Industry, Chemical Industry
Medical Uses
Pharmaceutical Industry
NA
Other Uses
Alloys
Alloys
Biological Properties
Toxicity
Highly Toxic
Highly Toxic
Present in Human Body
Yes
Yes
In Blood
7.00 Blood/mg dm-3
6
0.11 Blood/mg dm-3
12
In Bone
170.00 p.p.m.
6
0.33 p.p.m.
21
Physical Properties
Melting Point
419.58 °C
99+
1,857.00 °C
14
Boiling Point
907.00 °C
99+
2,672.00 °C
39
Appearance
Physical State
Solid
Solid
Color
Silvery Gray
Silver
Luster
Metallic
Metallic
Hardness
Mohs Hardness
2.50
14
8.50
1
Brinell Hardness
327.00 MPa
32
687.00 MPa
16
Vickers Hardness
Not Available
1,060.00 MPa
10
Speed of Sound
3,850.00 m/s
18
5,940.00 m/s
5
Optical Properties
Refractive Index
1.00
2
Not Available
Reflectivity
80.00 %
5
Not Available
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
Zn
Cr
Isotopes
Known Isotopes
25
14
21
18
Electronegativity
Pauling Electronegativity
1.65
19
1.66
18
Sanderson Electronegativity
2.23
6
1.66
14
Allred Rochow Electronegativity
1.66
7
1.56
10
Mulliken-Jaffe Electronegativity
1.65
11
Not Available
Allen Electronegativity
1.59
22
1.65
19
Electropositivity
Pauling Electropositivity
2.35
35
2.34
36
Ionization Energies
1st Energy Level
906.40 kJ/mol
6
26,130.00 kJ/mol
1
2nd Energy Level
1,733.30 kJ/mol
27
28,750.00 kJ/mol
1
3rd Energy Level
3,833.00 kJ/mol
12
34,230.00 kJ/mol
1
4th Energy Level
5,731.00 kJ/mol
11
37,066.00 kJ/mol
1
5th Energy Level
7,970.00 kJ/mol
9
97,510.00 kJ/mol
1
6th Energy Level
10,400.00 kJ/mol
9
105,800.00 kJ/mol
1
7th Energy level
12,900.00 kJ/mol
9
114,300.00 kJ/mol
1
8th Energy Level
16,800.00 kJ/mol
6
125,300.00 kJ/mol
1
9th Energy Level
19,600.00 kJ/mol
8
134,700.00 kJ/mol
1
10th Energy Level
23,000.00 kJ/mol
10
144,300.00 kJ/mol
1
11th Energy Level
26,400.00 kJ/mol
11
26,130.00 kJ/mol
12
12th Energy Level
29,990.00 kJ/mol
11
28,750.00 kJ/mol
13
13th Energy Level
40,490.00 kJ/mol
5
34,230.00 kJ/mol
10
14th Energy Level
43,800.00 kJ/mol
6
37,066.00 kJ/mol
12
15th Energy Level
47,300.00 kJ/mol
8
97,510.00 kJ/mol
1
16th Energy Level
52,300.00 kJ/mol
9
105,800.00 kJ/mol
2
17th Energy Level
55,900.00 kJ/mol
10
114,300.00 kJ/mol
3
18th Energy Level
59,700.00 kJ/mol
11
125,300.00 kJ/mol
4
19th Energy Level
67,300.00 kJ/mol
10
134,700.00 kJ/mol
5
20th Energy Level
171,200.00 kJ/mol
1
144,300.00 kJ/mol
7
21st Energy Level
179,100.00 kJ/mol
1
157,700.00 kJ/mol
7
22nd Energy Level
Not Available
166,090.00 kJ/mol
6
Electrochemical Equivalent
1.22 g/amp-hr
99+
0.32 g/amp-hr
99+
Electron Work Function
4.33 eV
17
4.50 eV
14
Other Chemical Properties
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility
Atomic Properties
Atomic Number
30
99+
24
99+
Electron Configuration
[Ar] 3d10 4s2
[Ar] 3d5 4s1
Crystal Structure
Hexagonal Close Packed (HCP)
Body Centered Cubic (BCC)
Crystal Lattice
HCP-Crystal-Structure-of-Zinc.jpg#100
BCC-Crystal-Structure-.jpg#100
Atom
Number of Protons
30
99+
24
99+
Number of Neutrons
35
99+
28
99+
Number of Electrons
30
99+
24
99+
Radius of an Atom
Atomic Radius
134.00 pm
99+
128.00 pm
99+
Covalent Radius
122.00 pm
99+
139.00 pm
99+
Van der Waals Radius
139.00 pm
99+
200.00 pm
28
Atomic Weight
65.38 amu
99+
52.00 amu
99+
Atomic Volume
9.20 cm3/mol
99+
7.23 cm3/mol
99+
Adjacent Atomic Numbers
Valence Electron Potential
38.90 (-eV)
99+
170.00 (-eV)
4
Lattice Constant
266.49 pm
99+
291.00 pm
99+
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
7.14 g/cm3
99+
7.19 g/cm3
99+
Density When Liquid (at m.p.)
6.57 g/cm3
37
6.30 g/cm3
40
Tensile Strength
Not Available
689.00 MPa
7
Viscosity
Not Available
Not Available
Vapor Pressure
Vapor Pressure at 1000 K
Not Available
0.00 (Pa)
24
Vapor Pressure at 2000 K
Not Available
774.00 (Pa)
1
Elasticity properties
Shear Modulus
43.00 GPa
18
115.00 GPa
9
Bulk Modulus
70.00 GPa
19
160.00 GPa
11
Young's Modulus
108.00 GPa
19
279.00 GPa
8
Poisson Ratio
0.25
24
0.21
32
Other Mechanical Properties
NA
NA
Magnetic Properties
Magnetic Characteristics
Specific Gravity
6.90
99+
7.19
99+
Magnetic Ordering
Diamagnetic
Antiferromagnetic
Electrical Properties
Electrical Property
Conductor
NA
Resistivity
59.00 nΩ·m
40
125.00 nΩ·m
27
Electrical Conductivity
0.17 106/cm Ω
12
0.08 106/cm Ω
25
Electron Affinity
0.00 kJ/mol
40
64.30 kJ/mol
15
Thermal Properties
Specific Heat
0.39 J/(kg K)
14
0.45 J/(kg K)
12
Molar Heat Capacity
25.47 J/mol·K
39
23.35 J/mol·K
99+
Thermal Conductivity
116.00 W/m·K
14
93.90 W/m·K
17
Critical Temperature
Not Available
Not Available
Thermal Expansion
30.20 µm/(m·K)
11
4.90 µm/(m·K)
99+
Enthalpy
Enthalpy of Vaporization
7.32 kJ/mol
99+
348.80 kJ/mol
24
Enthalpy of Fusion
7.32 kJ/mol
99+
15.31 kJ/mol
20
Enthalpy of Atomization
129.70 kJ/mol
99+
397.50 kJ/mol
21
Standard Molar Entropy
41.60 J/mol.K
36
23.80 J/mol.K
99+
|
||
|
||
|
