AHL Atomic
Structure: Ionization Energy
Slide 5 of 18
Ionization
–When the term
ionization (energy) is used in isolation, 1st ionization (energy) must be
understood.
Reverse of Ionization:
X+(g) + 1e-(g) ® X(g) n
= ¥ ® n = 1, DHq = - DHqIE
where, IE =
ionization energy
Electronic transition from ¥ ® 1 involves evolution
of energy in the form of light energy (as with every other
relaxation process).
Ionization energy therefore is the energy required to remove an
electron from a gaseous atom to produce a gaseous
ion.
Defined another way, it is the energy required to convert a mole of
gaseous atoms into a mole of positively charged gaseous
ions.