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Radium , including Technical Data, Safety Data and its high purity propertiesresearch, applications and other useful facts are discussed below. Scientific facts such as the atomic structure,ionization energyabundance on Earthconductivity and thermal properties are included.

Radium is a silvery metal that has a brilliant white color which quickly turns black when exposed to air. Formerly, radium was used in self-luminous or glow-in-the-dark paints for watches, clocks, instrument dials, nuclear panels and aircraft switches. After radium was deemed unsafe for human contact, it was no longer used in this capacity. Today, all radium is produced by the decay of other heavier elements and is found in minute amounts in theuranium ore uraninite and in thorium minerals. Radium is commercially obtained aschloride and bromide.

Radium is an S-Block, Group 2, Period 7 element. The number of electrons in each of Radium‘s shells is 2, 8, 18, 32, 18, 8, 2 and its electronic configuration is 1s2 2s2p6 3s2p6d10 4s2p6d10f145s2p6d10 6s2p6 7s2. In its elemental form Radium‘s CAS number is7440-14-4. The radium atom has a radius of and it‘s Van der Waals radius is 

Radium was discovered by Marie Sk?odowska-Curie and her husband Pierre on December 21, 1898 in pitchblende from North Bohemia. In 1910, through the electrolysis of a pure radium chloride solution by using a mercury cathode and distilling in an atmosphere of hydrogen gasradium, radium was isolated as a pure metal by Curie and André-Louis Debierne. In the beginning of the 20th Century, radium was first industrially produced by Biraco, a subsidiary company of Union Minière du Haut Katanga in Belgium. 

Abundance. The following table shows the abundance of radium and each of its naturally occurringisotopes on Earth along with the atomic mass for each isotope.
Isotope Atomic Mass % Abundance on Earth
Ra-223 223.018497 -
Ra-224 224.020202 -
Ra-225 225.023603 -
Ra-226 226.025403 (3) -
Ra-227 227.029170 -
Ra-228  228.031063 -

The following table shows the abundance of radium present in the human body and in the universe scaled to parts per billion (ppb) by weight and by atom:

  Typical Human Body Universe
by Weight 0.000001 ppb 0
by Atom 0.00000003 atoms relative to C = 1000000 -

Ionization Energy. The ionization energy for radium (the least required energy to release a single electron from the atom in it‘s ground state in the gas phase) is stated in the following table:
1st Ionization Energy 509.4 kJ mol-1
2nd Ionization Energy 979.1 kJ mol-1
3rd Ionization Energy kJ mol-1

Conductivity. As to radium‘s electrical and thermal conductivity, the electrical conductivity measured in terms of electrical resistivity @ 20 ?C is1 ?Ocm and its electronegativities (or its ability to draw electrons relative to other elements) is 0.9. The thermal conductivity of radium is 18.6 W m-1 K-1. 

Thermal Properties. The melting point and boiling point for radium are stated below. The following chart sets forth the heat of fusion, heat of vaporization and heat of atomization.
Heat of Fusion 8.5 kJ mol-1
Heat of Vaporization 113 kJ mol-1
Heat of Atomization 159 kJ mol-1

Formula Atomic Number Molecular Weight Electronegativity (Pauling) Density Melting Point Boiling Point Vanderwaals radius Ionic radius Energy of first ionization
Ra 88 [ 226 ] 0.9 5.5 g/cm3 700 °C 1500 °C 283pm 162 pm 509.4 kJ.mol-1