Element Information, Facts, Properties, Trends, Uses, Comparison with other elements
Radium is a chemical element with symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is almost colorless, but it readily combines with nitrogen (rather than oxygen) on exposure to air, forming a black surface layer of radium nitride (Ra3N2).
It belongs to group 2 of the periodic table having trivial name alkaline earth metals*.
Read key information and facts about element Radium
|Appearance||silvery white metallic|
|Classification||Alkaline Earth Metal|
|Group in Periodic Table||2|
|Group Name||beryllium family|
|Period in Periodic Table||period 7|
|Block in Periodic Table||s -block|
|Electronic Configuration||[Rn] 7s2|
|Electronic Shell Structure (Electrons per shell)||2, 8, 18, 32, 18, 8, 2|
|Melting Point||973 K|
|Boiling Point||2010 K|
How to Locate Radium on Periodic Table
Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 88 to find Radium on periodic table.
Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Radium on periodic table look for cross section of group 2 and period 7 in the modern periodic table.
The element Radium was discovered by P. and M. Curie in year 1898 in France. Radium was first isolated by M. Curie in 1902. Radium derived its name from the Latin radius, 'ray'.
The Curies reported on December 26, 1898, a new element different from polonium, which Marie later isolated fromuraninite.
Radium Presence: Abundance in Nature and Around Us
The table below shows the abundance of Radium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
|ppb by weight (1ppb =10^-7 %)||ppb by atoms (1ppb =10^-7 %)|
|Abundance in Universe||-||-|
|Abundance in Sun||-||-|
|Abundance in Meteorites||-||-|
|Abundance in Earth's Crust||0.00010||0.00001|
|Abundance in Oceans||0.00000001||0.0000000003|
|Abundance in Humans||0.000001||0.00000003|
Crystal Structure of Radium
The solid state structure of Radium is Body Centered Cubic.
The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.
Unit Cell Parameters
The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)
|514.8 pm||514.8 pm||514.8 pm|
and the angles between them Lattice Angles (alpha, beta and gamma).
The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.
The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.
|Space Group Name||Im_ 3m|
|Oxidation States||Space Group Number||229|
|Crystal Structure||Body Centered Cubic|
Radium Atomic and Orbital Properties
Radium atoms have 88 electrons and the electronic shell structure is [2, 8, 18, 32, 18, 8, 2] with Atomic Term Symbol (Quantum Numbers) 1S0.
|Number of Electrons (with no charge)||88|
|Number of Protons||88|
|Number of Neutrons||138|
|Shell structure (Electrons per energy level)||2, 8, 18, 32, 18, 8, 2|
|Electron Configuration||[Rn] 7s2|
|Main Oxidation States||2|
|Atomic Term Symbol (Quantum Numbers)||1S0|
Bohr Atomic Model of Radium - Electrons per energy level
Ground State Electronic Configuration of Radium - neutral Radium atom
Abbreviated electronic configuration of Radium
The ground state abbreviated electronic configuration of Neutral Radium atom is [Rn] 7s2. The portion of Radium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Rn]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 7s2, electrons in the outermost shell that determine the chemical properties of the element.
Unabbreviated electronic configuration of neutral Radium
Complete ground state electronic configuration for the Radium atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 7s2
Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.
Atomic Structure of Radium
Radium atomic radius is - , while it's covalent radius is - .
|Atomic Radius Calculated|
- (0 Å)
|Atomic Radius Empirical|
215 pm (2.15 Å)
|Atomic Volume||41.09 cm3/mol|
|Van der Waals Radius||283 pm|
|Neutron Cross Section||20|
|Neutron Mass Absorption||-|
Atomic Spectrum of Radium
Radium Chemical Properties: Radium Ionization Energies and electron affinity
The electron affinity of Radium is - .
Ionization Energy of Radium
Refer to table below for Ionization energies of Radium
|Ionization energy number||Enthalpy - kJ/mol|
Radium Physical Properties
Refer to below table for Radium Physical Properties
|Molar Volume||41.09 cm3/mol|
Hardness of Radium - Tests to Measure of Hardness of Element
Radium Electrical Properties
Radium is Conductor of electricity. Refer to table below for the Electrical properties ofRadium
|Electrical Conductivity||1000000 S/m|
|Resistivity||0.000001 m Ω|
Radium Heat and Conduction Properties
|Thermal Conductivity||19 W/(m K)|
Radium Magnetic Properties
|Mass Magnetic Susceptibility||-|
|Molar Magnetic Susceptibility||-|
|Volume Magnetic Susceptibility||-|
Optical Properties of Radium
Acoustic Properties of Radium
|Speed of Sound||-|
Radium Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Radium
|Melting Point||973 K (699.85°C, 1291.73 °F)|
|Boiling Point||2010 K (1736.85°C, 3158.33 °F)|
Enthalpies of Radium
|Heat of Fusion||8 kJ/mol|
|Heat of Vaporization||125 kJ/mol|
|Heat of Combustion||-|
Radium Isotopes - Nuclear Properties of Radium
Radium has 33 isotopes, with between 202 and 234 nucleons. Radium has 0 stable naturally occuring isotopes.
Isotopes of Radium - Naturally occurring stable Isotopes: -.
|Isotope||Z||N||Isotope Mass||% Abundance||T half||Decay Mode|