Zn+2NaOH+2H2O=Na2[Zn（OH）4]+H2↑ Zn2+4NH3.H2O=[Zn（OH）4]2-+4NH4+
Zn+2NaOH=2Na2ZnO2+H2Zn2+ +2NH3.H2O=Zn(OH)2+2NH4+ 沉淀符号和气体符号不好打
2Zn+2NaOH+2H2O=2Na2ZnO2+3H2（气体）Zn2+2NH3*H2O=Zn(OH）2(沉淀）+2NH4+
