Which of the following BEST describes the purpose of effective nuclear charge?
1. It is used to determine the number of
valence electrons of a given species.
2. It exists only to torture foolish CH 301
students who did not study.
3. It is a method to evaluate how much at-
traction a given electron "feels” from the nu-
cleus so that periodic trends can be predicted
and ratibnalized
4. It is a measure of how many protons a
given atom has which is useful because of
variations from isotope to isotope.
5. It is a measure of the effect of filled and
half-filled subshells on the stability of atoms
and ions.
6. It is used to rationalize chemical bonding
in covalently bonded molecules.