va rog rezolvarea la ex 2 multumescc

Răspuns:
A 1s2/2s2,2p6/3s2,3p6/4s2 Z=20 (metal)
B1s2/2s2,2p6/3s2,3p4 Z=16 (nemetal)
leg ionica AB
M AB=40+32=72
40g A..................................72g AB
80g......................................X
X=144g
Explicație: