Make your own free website on


Information valid for Ra-266 unless otherwise noted

Basic Information

Symbol: Ra
Atomic Number: 88
Mass: (226.0)
Melting Point: 700.0 C
Boiling Point: 1737.0 C
Number of Protons/Electrons: 88
Number of Neutrons: 138
Classification: Alkaline Earth
Crystal Structure: Cubic
Density @ 293 K: 5.0 g/cm3
Color: silverish

Atomic Structure

[Bohr Model of Radium]
Number of Energy Levels: 7

  1. First Energy Level: 2
    Second Energy Level: 8
    Third Energy Level: 18
    Fourth Energy Level: 32
    Fifth Energy Level: 18
    Sixth Energy Level: 8
    Seventh Energy Level: 2


Isotope Half Life
Ra-222 38.0 seconds
Ra-223 11.43 days
Ra-224 3.66 days
Ra-225 14.9 days
Ra-226 1600.0 years
Ra-228 5.76 years


Date of Discovery: 1898
Discoverer: Pierre and Marie Curie
Name Origin: From the Latin word radius (ray)
Uses: treating cancer
Obtained From: uranium ores