1> Xac dinh A , B, C, D, E va hoan thanh PTHH
a) A + Fe2O3 to ----> B + NaOH -----> C + HCl--->D + H2SO4 ----> E + Mg to-->A
b) A+Fe2O3 to ==> B+Cl2==>C+ NaOH==>D +to==>E+H2 to==>B
c) A + O2 ---> B + HCl --->C + NaOH ---> D +NaOH---> E +HCl --->D
to : nhiet do ( pu co nhiet do)
a)
2Al+Fe2O3\(\rightarrow\)Al2O3+2Fe
Al2O3+2NaOH\(\rightarrow\)2NaAlO2+H2O
NaAlO2+HCl+H2O\(\rightarrow\)Al(OH)3+NaCl
2Al(OH)3+3H2SO4\(\rightarrow\)Al2(SO4)3+6H2O
3Mg+Al2(SO4)3\(\rightarrow\)3MgSO4+2Al
A-Al, B-NaAlO2, C-Al(OH)3, D-Al2(SO4)3
b)
2Al+Fe2O3\(\rightarrow\)Al2O3+2Fe
2Fe+3Cl2\(\rightarrow\)2FeCl3
FeCl3+3NaOH\(\rightarrow\)Fe(OH)3+3NaCl
2Fe(OH)3\(\rightarrow\)Fe2O3+3H2O
Fe2O3+3H2\(\rightarrow\)2Fe+3H2O
A-Al, B-Fe, C-FeCl3, D-Fe(OH)3, E-Fe2O3
c)
4Al+3O2\(\rightarrow\)2Al2O3
Al2O3+6HCl\(\rightarrow\)2AlCl3+3H2O
AlCl3+3NaOH\(\rightarrow\)Al(OH)3+3NaCl
Al(OH)3+NaOH\(\rightarrow\)NaAlO2+2H2O
NaAlO2+HCl+H2O\(\rightarrow\)Al(OH)3+NaCl
A-Al, B-Al2O3, C-AlCl3, D-Al(OH)3, E-NaAlO2