![](http://www.alamy.com/thumbs/6/3E94565D-923A-4482-8AFD-AE4C33004096/2ACT1M0.jpg)
Radium (Ra). Diagram of the nuclear composition, electron configuration, chemical data, and valence (outer electron) orbitals of an atom of radium-226
Radium (Ra). Diagram of the nuclear composition, electron configuration, chemical data, and valence (outer electron) orbitals of an atom of radium-226 (atomic number: 88), the most stable isotope of this element. The nucleus consists of 88 protons (red) and 138 neutrons (orange). 88 electrons (white) successively occupy available electron shells (rings). Radium is a radioactive alkaline earth metal in group 2, period 7, and the s-block of the periodic table. Formed in uranium ores, the Curies discovered it in 1898. Radium-226, once used in watches, has a half-life of 1061 years, with the unstable nucleus emitting an alpha particle to form radon-222.
Size: 5197px × 5008px
Photo credit: © CARLOS CLARIVAN/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: -atomic, -block, 7, 7s, 7s2, alkaline, amu, atom, atomic, background, black, block, chemical, chemistry, configuration, data, diagram, earth, electron, electronic, electrons, element, elemental, elements, energy, function, illustration, isotope, level, levels, metal, metallic, metals, neutron, neutrons, nuclear, nucleon, nucleons, nucleus, number, orbital, orbitals, period, physical, pm, properties, property, proton, quantum, ra, radioactive, radioisotope, radioisotopes, radium, radium-226, radius, shell, shells, simple, solid, solids, structural, structure, subatomic, subshell, subshells, symbol, types, valence, wave, weight