Hypothesis 2, including explanation, for reactivity trend down a column:

Question


Metal reactivity will increase as you go down a group, because the nuclear shielding increases and causes the nucleus’ hold on the valence electron to weaken, therefore it is easier to remove the valence electrons. 



Is this right to you? It is what I came up with, I just wanted it checked. Anything added, etc.

Answer 1

That sounds OK to me but I think of it as the shielding effect coupled with the distance. The outer electrons is farther and farther out as one goes down the table for group I metals. That increasing distance means the attractive forces between the nucleus and the lone electron in the outer shell is weaker and weaker so it is easier to pull that last electron away. The shielding effect of the inner electrons means less attraction between the nucleus and the outer electron, too, so both contribute to removing the outermost electron.