Z=11--> 1atom are 11electroni=11protoni
1molatomi.Na...are masa 23g.....contine N,A= 6,o23x1o²³at(numarul lui Avogadro)
1,38g............N= 0,36x10²³atomi
1 atom............contine 11 protoni
0,36x10²³at..............x=...........................calculeaza !!!!