Ex 1. va rog dau coroana
![Ex 1 Va Rog Dau Coroana class=](https://ro-static.z-dn.net/files/d3d/ce836b548bca9de5a1bdd794b95fe224.jpg)
Răspuns:
P4+3O2=P4O6
Ca+2H2O=Ca(OH)2+H2
ZnSO4+2KOH=K2SO4+Zn(OH)2
N2O5+H2O=2HNO3