плиииииииииииииз 2 варианта​

4Na + O2 = 2Na2O
H2 + K2O =2K + H2O
Mg + 2HBr= MgBr2 +H2

2Ca + O2 = 2CaO
Mg + H2 = H2Mg

2CuO = 2Cu + O2
2HCl = H2 + 2Cl

Na + HBr = HNa + Br
CuO + H2 = Cu + H2O

Fe + 3Br = FeBr3
4Na + O2 = 2Na2O
CaO + H2 = Ca + H2O
2Al + 3MgO = 3Mg + Al2O3