C+O2=CO2

CO2+H2O=H2CO3

NaOH+H2CO3=Na2CO3+H2O

4Na+O2=2Na2O

Na2O+H2O=2NaOH

2NaOH+Cu(NO3)2=2NaNO3+Cu(OH)2

Другой лист:

BaCl2+Na2SO4=2NaCl+BaSO4

2HCl+Zn=ZnCl2+H2

2NaOH+H2SO4=Na2SO4+H2O

2Zn+O2=2ZnO

Cl2+H2=2HCl

MgO+2HCl=MgCl2+H2O