Numerical values
For each atom, the column marked 1 is the first ionization energy to ionize the neutral atom, the column marked 2 is the second ionization energy to remove a second electron from the +1 ion, the column marked 3 is the third ionization energy to remove a third electron from the +2 ion, and so on. "use" and "WEL" give ionization energy in the unitNotes
* Values from CRC are ionization energies given in the unit eV; other values are molar ionization energies given in the unitReferences
WEL
As quoted at http://www.webelements.com/ from these sources: * J.E. Huheey, E.A. Keiter, and R.L. Keiter in ''Inorganic Chemistry : Principles of Structure and Reactivity'', 4th edition, HarperCollins, New York, USA, 1993. * A.M. James and M.P. Lord in ''Macmillan's Chemical and Physical Data'', Macmillan, London, UK, 1992.External links
See also
* Molar ionization energies of the elements {{Navbox periodic table Properties of chemical elements Chemical element data pages