OFFSET
1,1
COMMENTS
The first ionization energy of an element X is the enthalpy change of X (g) -> X+ (g) + e-.
The values for chemical elements in each period (1 - 2, 3 - 10, 11 - 18, 19 - 36, 37 - 54, 55 - 86) are overall increasing, with boron group elements (boron, aluminum, gallium, indium, thallium) having relative low first ionization energies comparing with their nearby elements.
LINKS
NIST Atomic Spectra Database, Ionization Energies Form
EXAMPLE
The first ionization energies for hydrogen (1), helium (2) and lithium (3), etc. are 1312.0 kJ/mol, 2372.3 kJ/mol, 520.2 kJ/mol, etc.
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Jianing Song, Oct 13 2018
STATUS
approved