Radium

Definition of Radium: Is a radioactive chemical element, which has the symbol Ra. This is the common definition for Radium, other definitions can be discussed in the article

Notes

Its appearance is almost pure white, but it readily oxidizes on exposure to air, turning black. Radium is an alkaline earth metal that is found in trace amounts in uranium ores. It is extremely radioactive. Its most stable isotope has a half-life of 1602 years and decays into radon gas.