H2SO4+2NaOH=Na2SO4+2H2O
2H(+1)+SO4(-2)+2Na(+1)+OH(-1)=2Na(+1)+SO4(-2)+2H2O
2H(+1)+2OH(-1)=2H2O
CuCl2+2KOH=Cu(OH)2+2KCl
Cu(+2)+2Cl(-1)+2K(+1)+2OH(-1)=Cu(OH)2+2K(+1)+2Cl(-1)
Cu(+2)+2OH(-1)=Cu(OH)2
Na2CO3+2HCl=2NaCl+CO2+H2O
2Na(+1)+CO3(-2)+2H(+1)-Cl(-1)=2Na(+1)+2Cl(-1)+CO2+H2O
CO3(+2)+2H(+1)=CO2+H2O