Symbol
Ca
  
Cr
  
Period Number
4
  
4
  
Block
s block
  
d block
  
Element Family
Alkaline Earth
  
Transition Metal
  
Space Group Name
Fm_ 3m
  
Im_ 3m
  
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.
  
- 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
Humphry Davy
  
Louis Nicolas Vauquelin
  
Discovery
In 1808
  
In Between 1797 - 1798
  
Abundance
  
  
Abundance In Universe
1.5 * 10-3 %
  
7
Abundance In Earth's Crust
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.
  
- 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
Chemical Industry
  
Automobile Industry, Chemical Industry
  
Medical Uses
Dentistry, Pharmaceutical Industry
  
NA
  
Other Uses
Alloys
  
Alloys
  
Biological Properties
  
  
Toxicity
Non Toxic
  
Highly Toxic
  
Present in Human Body
Yes
  
Yes
  
In Blood
60.50 Blood/mg dm-3
  
4
0.11 Blood/mg dm-3
  
12
In Bone
170,000.00 p.p.m.
  
1
0.33 p.p.m.
  
21
Melting Point
1,857.00 °C
  
14
Boiling Point
1,484.00 °C
  
99+
2,672.00 °C
  
39
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Silver
  
Luster
NA
  
Metallic
  
Hardness
  
  
Brinell Hardness
170.00 MPa
  
99+
Vickers Hardness
Not Available
  
1,060.00 MPa
  
10
Speed of Sound
3,810.00 m/s
  
19
5,940.00 m/s
  
5
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available
  
Chemical Formula
Ca
  
Cr
  
Isotopes
  
  
Electronegativity
  
  
Pauling Electronegativity
Sanderson Electronegativity
Allred Rochow Electronegativity
Mulliken-Jaffe Electronegativity
Not Available
  
Electropositivity
  
  
Pauling Electropositivity
Ionization Energies
  
  
1st Energy Level
589.80 kJ/mol
  
99+
26,130.00 kJ/mol
  
1
2nd Energy Level
1,145.40 kJ/mol
  
99+
28,750.00 kJ/mol
  
1
3rd Energy Level
4,912.40 kJ/mol
  
7
34,230.00 kJ/mol
  
1
4th Energy Level
6,491.00 kJ/mol
  
7
37,066.00 kJ/mol
  
1
5th Energy Level
8,153.00 kJ/mol
  
7
97,510.00 kJ/mol
  
1
6th Energy Level
10,496.00 kJ/mol
  
8
105,800.00 kJ/mol
  
1
7th Energy level
12,270.00 kJ/mol
  
12
114,300.00 kJ/mol
  
1
8th Energy Level
14,206.00 kJ/mol
  
15
125,300.00 kJ/mol
  
1
9th Energy Level
18,191.00 kJ/mol
  
12
134,700.00 kJ/mol
  
1
10th Energy Level
20,385.00 kJ/mol
  
16
144,300.00 kJ/mol
  
1
11th Energy Level
57,110.00 kJ/mol
  
3
26,130.00 kJ/mol
  
12
12th Energy Level
63,410.00 kJ/mol
  
3
28,750.00 kJ/mol
  
13
13th Energy Level
70,110.00 kJ/mol
  
3
34,230.00 kJ/mol
  
10
14th Energy Level
78,890.00 kJ/mol
  
4
37,066.00 kJ/mol
  
12
15th Energy Level
86,310.00 kJ/mol
  
5
97,510.00 kJ/mol
  
1
16th Energy Level
94,000.00 kJ/mol
  
6
105,800.00 kJ/mol
  
2
17th Energy Level
104,900.00 kJ/mol
  
7
114,300.00 kJ/mol
  
3
18th Energy Level
111,711.00 kJ/mol
  
8
125,300.00 kJ/mol
  
4
19th Energy Level
Not Available
  
134,700.00 kJ/mol
  
5
20th Energy Level
Not Available
  
144,300.00 kJ/mol
  
7
21st Energy Level
Not Available
  
157,700.00 kJ/mol
  
7
22nd Energy Level
Not Available
  
166,090.00 kJ/mol
  
6
Electrochemical Equivalent
0.75 g/amp-hr
  
99+
0.32 g/amp-hr
  
99+
Other Chemical Properties
Chemical Stability, Flammability, Ionization, Solubility
  
Anti Corrosion, Chemical Stability, Ionization, Radioactive Isotopes, Solubility
  
Electron Configuration
[Ar] 4s2
  
[Ar] 3d5 4s1
  
Crystal Structure
Face Centered Cubic (FCC)
  
Body Centered Cubic (BCC)
  
Crystal Lattice
FCC-Crystal-Structure-of-Calcium.jpg#100
  
BCC-Crystal-Structure-.jpg#100
  
Atom
  
  
Radius of an Atom
  
  
Atomic Volume
29.90 cm3/mol
  
7
7.23 cm3/mol
  
99+
Adjacent Atomic Numbers
  
  
Valence Electron Potential
29.00 (-eV)
  
99+
170.00 (-eV)
  
4
Lattice Angles
π/2, π/2, π/2
  
π/2, π/2, π/2
  
Lattice C/A Ratio
Not Available
  
Not Available
  
Density
  
  
Density At Room Temperature
1.55 g/cm3
  
99+
7.19 g/cm3
  
99+
Density When Liquid (at m.p.)
1.38 g/cm3
  
99+
Tensile Strength
Not Available
  
Viscosity
Not Available
  
Not Available
  
Vapor Pressure
  
  
Vapor Pressure at 2000 K
Not Available
  
Elasticity properties
  
  
Other Mechanical Properties
NA
  
NA
  
Magnetic Characteristics
  
  
Magnetic Ordering
Diamagnetic
  
Antiferromagnetic
  
Electrical Properties
  
  
Electrical Property
Conductor
  
NA
  
Resistivity
33.60 nΩ·m
  
99+
125.00 nΩ·m
  
27
Electrical Conductivity
0.30 106/cm Ω
  
6
0.08 106/cm Ω
  
25
Electron Affinity
2.37 kJ/mol
  
39
64.30 kJ/mol
  
15
Specific Heat
0.63 J/(kg K)
  
7
0.45 J/(kg K)
  
12
Molar Heat Capacity
25.93 J/mol·K
  
34
23.35 J/mol·K
  
99+
Thermal Conductivity
201.00 W/m·K
  
5
93.90 W/m·K
  
17
Critical Temperature
Not Available
  
Not Available
  
Thermal Expansion
22.30 µm/(m·K)
  
19
4.90 µm/(m·K)
  
99+
Enthalpy
  
  
Enthalpy of Vaporization
150.00 kJ/mol
  
99+
348.80 kJ/mol
  
24
Enthalpy of Fusion
8.54 kJ/mol
  
99+
15.31 kJ/mol
  
20
Enthalpy of Atomization
184.00 kJ/mol
  
99+
397.50 kJ/mol
  
21
Standard Molar Entropy
41.60 J/mol.K
  
36
23.80 J/mol.K
  
99+