Note: Spike = change in quantum shell, spike between 1st and 2nd I.E. means it is a Group I element.
Try it yourself!
The ionization energies of a singly charged cation are as follows (in kJmol-1):
1600, 3200, 4400, 16100, 19800 and 23800.
What is the valence electronic configuration of the element?
|A||ns1||B||ns2 np1||C||ns2 np2||D||ns2 np3|
Ans: This is a singly charged cation so spike is therefore between 4th and 5th I.E., so it is a Group IV element.