Symbol
Ra
Pb
Group Number
214
0
17
👆🏻
Period Number
76
2
7
👆🏻
Block
s block
p block
Element Family
Alkaline Earth
Post-Transition
CAS Number
74401447439921
7429905
54386242
👆🏻
Space Group Name
Im_ 3m
Fm_ 3m
Space Group Number
229.00225.00
11
276
👆🏻
Interesting Facts
- Radium metal is the heaviest metal of Alkaline earth metals column.
- Radium metal is highly radioactive and does not have any stable isotopes.
- Galena mineral contains almost 87% of Lead metal in it, Galena is sulfide mineral.
- The best available source of Lead metal today is by recycling automobile batteries.
Sources
Mining, Ores of metals
Earth's crust, Found in Minerals, Mining, Ores of metals, Ores of Minerals
History
Who Discovered
-
-
Discovery
In 1898
In Middle Easterns (7000 BCE)
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
0.00 %0.00 %
0
0.1
👆🏻
Abundance In Meteorites
-0.00 %
0
22
👆🏻
Abundance In Earth's Crust
0.00 %0.00 %
1E-37
8.1
👆🏻
Abundance In Oceans
0.00 %0.00 %
0
1.1
👆🏻
Abundance In Humans
0.00 %0.00 %
0
1.4
👆🏻
Uses & Benefits
- It is a highly radioactive metal; and sometime Radium-223 is used to treat prostate cancer.
-
It is used in luminous paints.
- It is also used in insecticides, hair dyes and as an anti-knocking additive for petrol. But all these are banned by the government as Lead metal is known for detrimental to health.
Industrial Uses
-
Chemical Industry, Electrical Industry, Electronic Industry
Medical Uses
Pharmaceutical Industry
Surgical Instruments Manufacturing
Other Uses
-
Alloys
Biological Properties
Toxicity
Highly Toxic
Toxic
Present in Human Body
✔
✘
✔
✘
In Blood
0.00 Blood/mg dm-30.21 Blood/mg dm-3
0
1970
👆🏻
In Bone
0.00 p.p.m.30.00 p.p.m.
0
170000
👆🏻
Melting Point
700.00 °C327.50 °C
-38.83
3410
👆🏻
Boiling Point
1,737.00 °C1,740.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery White
Gray
Luster
Metallic
Metallic
Hardness
Mohs Hardness
1.001.50
0.2
8.5
👆🏻
Brinell Hardness
700.00 MPa38.00 MPa
0.14
3490
👆🏻
Vickers Hardness
140.00 MPa38.00 MPa
0
3920
👆🏻
Speed of Sound
3,150.00 m/s1,190.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.002.02
0.155
3.41
👆🏻
Reflectivity
83.00 %5.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Ra
Pb
Isotopes
Known Isotopes
3335
0
38
👆🏻
Electronegativity
Pauling Electronegativity
0.901.87
0
2.6
👆🏻
Sanderson Electronegativity
0.892.29
0.22
2.56
👆🏻
Allred Rochow Electronegativity
0.971.55
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
0.922.41
0.62
2.48
👆🏻
Allen Electronegativity
0.891.85
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
3.101.67
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
509.30 kJ/mol715.60 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
979.00 kJ/mol1,450.50 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
509.30 kJ/mol3,081.50 kJ/mol
392.8
34230
👆🏻
4th Energy Level
5,093.00 kJ/mol4,083.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
5,090.00 kJ/mol6,640.00 kJ/mol
392
97510
👆🏻
6th Energy Level
5,090.00 kJ/mol7,150.00 kJ/mol
1007
105800
👆🏻
7th Energy level
5,090.00 kJ/mol7,156.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
5,090.00 kJ/mol7,150.00 kJ/mol
730
125300
👆🏻
9th Energy Level
5,090.00 kJ/mol7,156.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
5,090.00 kJ/mol7,156.00 kJ/mol
392
144300
👆🏻
11th Energy Level
5,090.00 kJ/mol7,156.00 kJ/mol
392
169988
👆🏻
12th Energy Level
5,090.00 kJ/mol7,150.00 kJ/mol
0
189368
👆🏻
13th Energy Level
5,090.00 kJ/mol7,150.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
5,090.00 kJ/mol715.60 kJ/mol
380
86450
👆🏻
15th Energy Level
50,900.00 kJ/mol71,500.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
50,900.00 kJ/mol71,500.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
509.30 kJ/mol715.60 kJ/mol
375.7
122200
👆🏻
18th Energy Level
5,090.00 kJ/mol7,150.00 kJ/mol
0
134810
👆🏻
19th Energy Level
509.30 kJ/mol715.60 kJ/mol
375.7
148700
👆🏻
20th Energy Level
509.00 kJ/mol715.00 kJ/mol
0
171200
👆🏻
21st Energy Level
509.30 kJ/mol715.60 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
509.00 kJ/mol715.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
509.30 kJ/mol715.60 kJ/mol
357.6
198800
👆🏻
24th Energy Level
509.30 kJ/mol715.60 kJ/mol
297.3
195200
👆🏻
25th Energy Level
509.00 kJ/mol715.00 kJ/mol
0
121900
👆🏻
26th Energy Level
509.30 kJ/mol715.60 kJ/mol
357.6
127700
👆🏻
27th Energy Level
509.30 kJ/mol715.60 kJ/mol
0
133800
👆🏻
28th Energy Level
509.30 kJ/mol715.60 kJ/mol
297.3
139800
👆🏻
29th Energy Level
509.30 kJ/mol715.60 kJ/mol
0
148100
👆🏻
30th Energy Level
509.00 kJ/mol715.00 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
4.22 g/amp-hr3.87 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
4.30 eV4.25 eV
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes, Radioactivity
Anti Corrosion, Ionization, Radioactive Isotopes
Atomic Number
8882
3
117
👆🏻
Electron Configuration
[Rn] 7s2
[Xe] 4f14 5d10 6s2 6p2
Crystal Structure
Body Centered Cubic (BCC)
Face Centered Cubic (FCC)
Crystal Lattice
Atom
Number of Protons
8882
3
117
👆🏻
Number of Neutrons
138125
4
285
👆🏻
Number of Electrons
8882
3
117
👆🏻
Radius of an Atom
Atomic Radius
215.00 pm175.00 pm
0
348
👆🏻
Covalent Radius
221.00 pm146.00 pm
0
260
👆🏻
Van der Waals Radius
283.00 pm202.00 pm
0
348
👆🏻
Atomic Weight
226.00 amu207.20 amu
6.94
294
👆🏻
Atomic Volume
45.20 cm3/mol18.17 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
20.10 (-eV)24.20 (-eV)
0
392.42
👆🏻
Lattice Constant
514.80 pm495.08 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, π/2
π/2, π/2, π/2
Lattice C/A Ratio
1.571.51
0.423
1.9
👆🏻
Density
Density At Room Temperature
5.50 g/cm311.34 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
5.50 g/cm310.66 g/cm3
0.512
41
👆🏻
Tensile Strength
40.00 MPa12.00 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)1.64 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
0.00 (Pa)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
25.00 GPa5.60 GPa
1.3
222
👆🏻
Bulk Modulus
43.00 GPa46.00 GPa
0
462
👆🏻
Young's Modulus
83.00 GPa16.00 GPa
0
528
👆🏻
Poisson Ratio
0.310.44
0.032
0.47
👆🏻
Other Mechanical Properties
-
Ductile, Malleable
Magnetic Characteristics
Specific Gravity
5.0011.35
0.53
4500
👆🏻
Magnetic Ordering
Nonmagnetic
Diamagnetic
Permeability
0.00 H/m0.00 H/m
1.25643E-06
0.0063
👆🏻
Susceptibility
0.000.00
-0.000166
200000
👆🏻
Electrical Properties
Electrical Property
-
Poor Conductor
Resistivity
100.00 nΩ·m208.00 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.00 106/cm Ω0.05 106/cm Ω
0
0.63
👆🏻
Electron Affinity
0.90 kJ/mol35.10 kJ/mol
0
222.8
👆🏻
Specific Heat
0.12 J/(kg K)0.13 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
20.05 J/mol·K26.65 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
18.60 W/m·K35.30 W/m·K
0
429
👆🏻
Critical Temperature
973.00 K600.61 K
26.3
3695
👆🏻
Thermal Expansion
8.50 µm/(m·K)28.90 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
113.00 kJ/mol179.40 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
8.60 kJ/mol4.77 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
163.00 kJ/mol194.60 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
71.00 J/mol.K64.80 J/mol.K
9.5
198.1
👆🏻