Đáp án + Giải thích các bước giải:

 a. $MnO_2 + 4HCl \longrightarrow MnCl_2 + Cl_2 + 2H_2O$

$2Fe + 3Cl_2 \overset{t^o}{\longrightarrow} 2FeCl_3$
$FeCl_3 + 3NaOH \longrightarrow Fe(OH)_3 \downarrow + 3NaCl$

$2NaCl + 2H_2O \xrightarrow{đpdd}{cmn} 2NaOH + H_2 \uparrow + Cl_2 \uparrow$

$Cl_2 + H_2O \rightleftharpoons HCl + HClO$

$HCl + AgNO_3 \longrightarrow HNO_3 + AgCl \downarrow$

b. $2KMnO_4 + 16HCl \longrightarrow 2KCl + 2MnCl_2 + 5Cl_2 + 8H_2O$

$Cl_2 + H_2O \rightleftharpoons HCl + HClO$

$Fe_2O_3 + 6HCl \longrightarrow 2FeCl_3 + 3H_2O$

$FeCl_3 + 3AgNO_3 \longrightarrow Fe(NO_3)_3 + 3AgCl \downarrow$

$2AgCl \overset{t^o}{\longrightarrow} 2Ag + Cl_2$

$Cl_2 + 2NaBr \longrightarrow 2NaCl + Br_2$
$Br_2 + 2HI \longrightarrow 2HBr + I_2$

c. $2KMnO_4 + 16HCl \longrightarrow 2KCl + 2MnCl_2 + 5Cl_2 + 8H_2O$

$Cl_2 + H_2O \rightleftharpoons HCl + HClO$

$HCl + Fe \longrightarrow FeCl_2 + H_2$

$FeCl_2 + 2AgNO_3 \longrightarrow Fe(NO_3)_2 + 2AgCl \downarrow$
$2AgCl \overset{t^o}{\longrightarrow} 2Ag + Cl_2$

d. $4HCl + MnO_2 \longrightarrow MnCl_2 + Cl_2 + 2H_2O$

$2Fe + 3Cl_2 \overset{t^o}{\longrightarrow} 2FeCl_3$
$FeCl_3 + 3NaOH \longrightarrow Fe(OH)_3 \downarrow + 3NaCl$

$2Fe(OH)_3 + 3H_2SO_4 \longrightarrow Fe_2(SO_4)_3 + 6H_2O$