why periodic trends are observed
chemical reactivity is determined mainly by valence electron why
shielding or screening
shielding is the presence of core electrons reduces the attraction valence electrons fell for the nucleus
outer electrons feel less possitive charge from the nucleus
recall : nuclear change is deetermined by the number of protons in the nucleus
Zeff is the positive charge an electron actually experiences from the nucleus
the effective nuclear chage is always less than
this is because core electrons are in the way
How dose this work
emit