Data Revision

Question 1

1) .Contribution of electrons excluding test electron in the (ns,np) group shields the valence electron to the extent of? Any special case mention?
2) . Contribution of electrons in (n-1) shell
3) . (n-2) or lower shells

Answer 1

1) . 0.35 except for 1s orbital which acts as (ns) in Helium and has found to contribute 0.30
2) . 0.85
3) 1