Na2CO3+2HCl--->2NaCl+H2O+CO2
Na2CO3+BaCl2---->2NaCl+BaCO3
H2SO4+2NaOH--->Na2SO4+2H2O
H2SO4+BaCl2--->BaSO4+2HCl
2NaOH+CuSO4---->Na2SO4+Cu(OH)2
BaCl2+CuSO4---->BaSO4+CuCl2
Vậy có 6 cặp chất td vs nhau
\(\text{Na2CO3+H2SO4->Na2SO4+CO2+H2O}\)
\(\text{Na2CO3+BaCl2->BaCO3+2NaCl}\)
\(\text{Na2CO3+CuSO4->CuCO3+Na2SO4}\)
\(\text{H2SO4+2NaOH->Na2SO4+2H2O}\)
\(\text{H2SO4+BaCl2->BaSO4+2HCl}\)
\(\text{NaOH+CuSO4->Cu(OH)2+Na2SO4}\)
\(\text{BaCl2+CuSO4->BaSO4+CuCl2}\)