Question

Exercitiul 4.2, am nevoie pana maine

Answer 1

2.  2+ 1=3    nr .de lectroni=nr. protoni, la elementul din casuta 3-Litiu

3. 2+2=4     nr.de electroni=nr.protoni, la elementul din casuta 4-Beriliu

4...........5......................................................................................................5-Bor

5.  ........6.......................................................................................................6-Carbon

6...........7........................................................................................................7- Azot)N)

7............8......................................................................................................8-FLuor