What is Radium
A highly radioactive and naturally-occurring metal, radium (pronounced as RAY-dee-em) is formed when uranium and thorium undergo disintegration in the environment. Represented by the chemical symbol Ra, it is classified in the family of alkaline earth metals . It has 33 isotopes of which Ra-226 and Ra-228 have a half-life of 1600 years and 5.75 years, respectively .
Where is the Element Found
Since the element is found in most uranium ores, especially in Canada and Democratic Republic of Congo, it can be obtained as a byproduct of uranium refining. Another source of radium is the spent fuel rods of nuclear reactors .
Origin of its Name: It is derived from the Latin word ‘radius’ that means ray .
Who Discovered Radium: Renowned scientists Marie Curie and Pierre Curie were the discoverers 
When, Where, and How was it Discovered
Marie Curie had observed that pitchblende (uranium oxide) was more radioactive even after extracting uranium from it. In 1898, the Curie couple used some chemical separation techniques to isolate radium from ten tons of the pitchblende that displayed new lines in its atomic spectrum. They were fascinated to find it glow with a faint blue light in the dark due to its high radioactivity .
In 1911, Marie Curie and Andre Debierne carried out electrolysis of radium chloride where a mercury cathode was used to isolate the metal .
|Atomic number||88 |
|CAS number||7440-14-4 |
|Position in the periodic table ||Group||Period||Block|
Classification, Properties and Characteristics of Radium
|Relative atomic mass|| |
|Atomic mass/weight||226 atomic mass units |
|Molar mass||223.018 g/mole |
|Color/appearance||Silver white |
|Melting point/freezing point||696°C (1285°F) |
|Boiling point||1500°C (2732°F) |
|Density||5 g/cm3 |
|Normal phase at room temperature (solid/liquid/gas)||Solid |
Atomic Data of Radium (Element 88)
|Valence electrons||2 |
|Quantum numbers |
|Electron configuration (noble gas configuration)||[Rn] 7s2|
|Atomic structure |
|– Number of Electrons||88|
|– Number of Neutrons||138|
|– Number of Protons||88|
|Radius of atom|
|– Atomic Radius||2.83 Å |
|– Covalent Radius||2.11 Å |
|Ionization energy