Na2CO3 + Ca(OH)2 \(->CaCO3\downarrow+2NaOH\)
2HCl + CaSO3 - > CaCl2 + SO2\(\uparrow\) + H2O
2NaOH + FeCl2 - > Fe(OH)2\(\downarrow\) + 2NaCl
BaCl2 + Na2CO3 - > BaCO3\(\downarrow\) + 2NaCl
AgNO3 + NaCl - > AgCl\(\downarrow\) + NaNO3
đề thiếu thiếu sao ấy ...:v