a)MnO2+4HCl=>Cl2+MnCl2+2H20

3Cl2+2Fe=>2FeCl3

FeCl3+3AgNO3=>3AgCl+Fe(NO3)3

b)  HCl+NaOH=>NaCl+H20

2NaCl+2H20=>Cl2+2NaOH+H2

Cl2+Cu=>CuCl2

c)  2HCl+ZnO=>ZnCl2+H20

ZnCl2+2AgNO3=>2AgCl+Zn(NO3)3

2AgCl+CuO=>CuCl2+Ag2O

d)  2NaCl+2H20=>Cl2+NaOH+H2

Cl2+H2=>2HCl

3HCl+FeCl3=>FeCl3+3HCl

Giải thích các bước giải:

a, 

(1) MnO2+ 4HCl -> MnCl2+ Cl2+ 2H2O 

(2) 2Fe+ 3Cl2 $\buildrel{{t^o}}\over\longrightarrow$ 2FeCl3 

(3) FeCl3+ 3AgNO3 -> Fe(NO3)3+ 3AgCl 

b, 

NaOH+ HCl -> NaCl+ H2O 

2NaCl $\buildrel{{đpnc}}\over\longrightarrow$ 2Na+ Cl2 

Cu+ Cl2 $\buildrel{{t^o}}\over\longrightarrow$ CuCl2

c, 

(1) Zn+ 2HCl -> ZnCl2+ H2 

(2) ZnCl2+ 2AgNO3 -> Zn(NO3)2+ 2AgCl 

d, 

(1) 2NaCl $\buildrel{{dpnc}}\over\longrightarrow$ 2Na+ Cl2 

(2) H2+ Cl2 $\buildrel{{askt}}\over\longrightarrow$ 2HCl 

(3) Fe2O3+ 6HCl -> 2FeCl3+ 3H2O