a.
raza atomica creste:
in perioade: de la dreapta la stanga
in grupe: de sus in jos
=> N, C, Li, Br, Ca, Sr
----------------------------->
creste raza atomica
b.
metale sunt: Li, Ca si Sr
₃Li: 1s2 2s1 _-e_> 1s2
₂₀Ca: 1s2 2s2 2p6 3s2 3p6 4s2 __-2e-_> 1s2 2s2 2p6 3s2 3p6
₃₈Sr: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 _-2e-_> 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6
c.
Li⁺: 1s2
Ca⁺²: 1s2 2s2 2p6 3s2 3p6
Sr⁺²: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6
d.
nici unul, toti cationii prezinta config. stabile de gaze rare diferite
e.
Li⁺: 1s2 => Z=2 => He
Ca⁺²: 1s2 2s2 2p6 3s2 3p6 => Z=18 => Ar
Sr⁺²: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 => Z=36 => Kr
