a) Cả 4 chất
$2AgNO_{3}$ + $CaOH_{2}$ → 2AgOH + Ca$(NO_{3})$$_{2}$
3$Ca(OH)_{2}$ + 2$FeCl_{3}$ → 3$CaCl_{2}$ + $2Fe(OH)_{3}$
$ZnSO_{4}$ + $Ca(OH)_{2}$ → $Zn(OH)_{2}$ + $CaSO_{4}$
$2Na_{2}$$SO_{3}$ + $Ca(OH)_{2}$ → 2NaOH + $CaSO_{3}$
b) Có 2 chất: $2AgNO_{3}$, $2Na_{2}$$SO_{3}$
HCl + $2Na_{2}$$SO_{3}$ → AgCl + $HNO_{3}$
HCl + $2AgNO_{3}$ → 2NaCl + $SO_{2}$ + $H_{2}$O
c) Có 3 chất: 2$FeCl_{3}$, $ZnSO_{4}$, $2Na_{2}$$SO_{3}$
$3Pb(NO_{3}$)$_{2}$ + 2$FeCl_{3}$ → $2Fe(NO_{3}$)$_{3}$ + $2PbCl_{2}$
$Pb(NO_{3}$)$_{2}$ + $ZnSO_{4}$ → $Zn(NO_{3}$)$_{2}$ + $PbSO_{4}$
$Pb(NO_{3}$)$_{2}$ + $Na_{2}$$SO_{3}$ → $PbSO_{3}$ + $2NaNO_{3}$
Cho cái hay nhất nha
